I had a PC system based on an ASRock Z97 chipset motherboard with a Haswell generation i7 processor and integrated graphics.  Before considering the system stable, I was attempting to do a stress test using the latest version of UBCD (version V5.3.9 at the time of this writing).  For these tests, I used Rufus to burn the ISO to a USB disk.

As expected, when booting from the thumbdrive, I had to select the non-UEFI version, otherwise the system would kick back to the boot menu.

Once loaded into UBCD, I found that Prime95 as well as choosing many other options under the CPU category would fail to load. Upon selecting an option, the system would immediately black screen and then automatically restart.   However the Memory -> Memtest86 option worked fine and was completely stable.

I tried many things to resolve the issue such as resetting all BIOS options to default, a different thumb drive, different processor (i5, another Devil’s Canyon Haswell) and a different power supply.  None of these fixed it.

As another test I booted the system into Windows 10 and it looped Prime95 without a problem, so I kept digging.

During my research, I stumbled upon a support thread on the UBCD forums, specifically this post:

https://www.ultimatebootcd.com/forums/viewtopic.php?p=11119#p11119

All of the tests that were failing were due to depending on CPUstress, which is launched by syslinux. This includes:

• CPUburn
• CPU Burn-in
• CPUinfo
• Intel Optimized LINPACK Benchmark
• Mersenne Prime Test (prime95)
• Stress
• StressCPU
• System Stability Tester

On the otherhand, the options that were functional included:

• CPUID
• x86test
• Intel Processor Frequency ID
• Intel Process Identification Utility

A workaround for the failing tests is to first select the desired test, press tab key and then change the first part of the commandt from:

/ubcd/boot/cpustress/bzImage

to:

/pmagic/bzImage

Then press enter. This managed to get the CPU test loaded (in this case Mersenne Prime test), however the USB keyboard stopped working and I couldn’t answer the prompts to begin the test.   I immediately plugged in a PS/2 keyboard and was able to get it working that way.

Another workaround I discovered was installing a dedicated video card. With the GPU installed, everything worked as expected without modifying the boot loader.

However if you don’t have a discrete GPU available, the final fix I found a workaround in the BIOS.

My motherboard had an option to set the amount of memory to dedicate to the integrated graphics processor built into the CPU (Advanced -> Chipset Configuration -> Share Memory).  By default this option is set to Auto.  The fix is to set it to a specific value that is between 32MB and 128MB. Setting it to 256MB would fail in the same way as Auto.

Once that is set, reboot, boot up UBCD and try the CPU test again!

You may find updating the firmware on an enterprise class Samsung PM863a SSD difficult. In this case I had a specific part number of MZ7LM3T8HMLP-00003.

The first step is to check the label on the drive and look for the version of F/W.

In my case I had GXT5003Q.   The second to last digit of the firmware is important because the number 3 represents a non SED model while a number 4 represents an SED model (Self Encrypting Drive).

The next step is to boot up  Windows based system with the drive installed. I found that Samsung Magician didn’t support the drive and simply shows “N/A.” I also tried an older command line application called SSDManager, but received the error: Detect Security Vulnerablility.

What finally worked with this drive was the application Samsung DC Toolkit. The software is available at the link below, (near the bottom of the page) and under the section Samsung SSD Toolkit for Data center:

https://semiconductor.samsung.com/us/consumer-storage/support/tools/

There are 2 published versions of the software. For a PM863a drive, you will need version 2.x per the documentation:

Samsung SSD DC Toolkit Version 2.1 is designed to work with Samsung SSD products including PM863, PM863a, SM863, SM863a, PM963 non-customized, 860 DCT, 883 DCT, 983 DCT, 983 DCT M.2 and 983 ZET. This software is not compatible with other manufacturers’ SSDs. 

For this guide, I used version 2.1.W.Q.0 of Samsung DC Toolkit.  A direct link is below:
https://semiconductor.samsung.com/resources/software-resources/Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe

Save this toolkit executable to a convenient location. It is portable and does not need to be installed.

Open a command prompt with Administrator privileges. Then navigate to the location of the download. Run the executable via the command line and you should be presented with something similar to:

================================================================================================
Samsung DC Toolkit Version 2.1.W.Q.0
Copyright (C) 2017 SAMSUNG Electronics Co. Ltd. All rights reserved.
================================================================================================
Usage: Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe [operation] …

Allowed Operations:
————————————————————————————————
-L [ –list ] Shows disks attached to the system
-I [ –info ] Displays the disk details
-ID [ –identify ] Shows Identify Informations
-F [ –firmware-update ] Updates firmware to specified disk
-E [ –erase ] Securely Erases all data from specified disk
-S [ –smart ] Shows SMART values of specified disk
-M [ –setmax ] Perform SetMax related operations on specified disk
-X [ –sct ] Executes SCT Commands on specified disk
-V [ –vendor-utility ] Execute Vendor Unique command on specified disk
-NG [ –nvme-get-log-pages ] Display Log Pages on specified NVMe disk
-NF [ –nvme-format-namespace ] Execute format command on specified NVMe disk
-NM [ –nvme-management-namespace ] Execute management command on specified NVMe disk
-ND [ –nvme-firmware-download ] Updates firmware to specified NVMe disk
-NC [ –nvme-firmware-commit ] Commit the firmware image on specified NVMe disk
-NV [ –nvme-vendor-utility ] Execute Vendor Unique command on specified NVMe disk
-HM [ –health-monitor ] Execute Health Monitor feature.
-C [ –command-history ] Shows history of the previously executed commands
-H [ –help ] Shows detailed help
————————————————————————————————

The first step is to run it again, but add the list option -L to generate a list of all available disks. The output should be similar to the below:

================================================================================================
Samsung DC Toolkit Version 2.1.W.Q.0
Copyright (C) 2017 SAMSUNG Electronics Co. Ltd. All rights reserved.
================================================================================================
—————————————————————————————————————————————————————————-
| Disk | Path | Model | Serial | Firmware | Optionrom | Capacity | Drive | Total Bytes | NVMe Driver |
| Number | | | Number | | Version | | Health | Written | |
—————————————————————————————————————————————————————————-
| 0 | \\.\PHYSICALDRIVE0 | SAMSUNG MZ7LM3T8HMLP-00003 | <serial number> | GXT5003Q | N/A | 3576 GB | GOOD | 1360.29 TB | N/A |
—————————————————————————————————————————————————————————-

Make note of the drive number in the list. In the example above, there was only a single drive in the machine so the drive number was assigned 0.

The next step is to download the appropriate firmware.  The SED and non SED firmwares are both available at the link below (GXT5103Q_nonSED.bin and GXT5404Q.bin).  Since the drive in my possession was a non SED model, I used the latest number 3 firmware available: GXT5103Q.

https://c.gmx.net/@324567863383819227/SlDWEtrmRueJ4nCqdGfOsQ/1186031158467499200

Save the firmware to the same location as the toolkit executable.

To upgrade the firmware, we will be using the -F option.  If you run the toolkit executable with just this flag, you will see something similar to the below:

————————————————————————————————
Usage:
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d [diskindex] -F [ –firmware-update ] [parameter-list]

Example:
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe –disk 1 –firmware-update –fwpackage-path /path/dsrdenc
[or] Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d 1 -F -p /path/dsrdenc
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe –disk 1 –firmware-update –fwpackage-path /path/dsrdenc
[or] Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d 1 -F -p /path/dsrdenc
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe –disk 1 –firmware-update –fwpackage-path /path/dsrdenc
[or] Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d 1 -F -p /path/dsrdenc
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe –disk 1 –firmware-update –fwpackage-path /path/dsrdenc –force
[or] Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d 1 -F -p /path/dsrdenc –force
Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe –disk A –firmware-update –fwpackage-path /path/dsrdenc –source “ABCD1234” (–force)
[or] Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -d A -F -p /path/dsrdenc -s “ABCD1234” (–force)

Sub Options:
-d [ –disk ] Disk-Number of the disk or A to select all supported disks to update firmware on.
-p [ –fwpackage-path ] Path to the FW binary file.
–force [ –force ] Enables the user to perform Firmware Download without prompting for any confirmations.
-s [ –source ] source firmware revision, use with option ‘A'(update multiple devices at ones).
A [ A ] updating all SATA devices(except primary device) to specific target firmware, use character ‘A’ instead of disk number.
————————————————————————————————

Here we can see we need 2 additional sub options for the firmware update, -d and -p. This will allow us to specify which disk number (from our previous list output) and also the location of the firmware (downloaded earlier).

Perform the firmware upgrade on the drive.  In this example, I used:

Samsung_SSD_DC_Toolkit_for_Windows_V2.1.exe -F -p GXT5103Q_nonSED.bin -d 0

Proceed by providing a yes confirmation.

If the flash was successful, you should see an output similar to the below:

————————————————————————————————
[[ WARNING ]]

Please Note that Firmware Update may format the disk and you will lose your data.
Please Ensure that data backup is taken before proceeding to Firmware Update.
If you are sure then only proceed, otherwise restart the application after taking a backup.
Continue Firmware Update ? [ yes ]: yes
————————————————————————————————
[F/W Update] Disk is Updated with the New Firmware.
————————————————————————————————
[F/W Update] Success
————————————————————————————————

Power cycle the machine, and you should now be running the latest firmware!

Notes:
If you try to flash an SED firmware on a non SED drive (or vice versa), then the firmware update will fail and you will receive this error:

————————————————————————————————
[ERROR] Firmware Update Failed Due to a failure in device interaction.
————————————————————————————————
[F/W Update] Failure
————————————————————————————————

References:
https://forums.servethehome.com/index.php?threads/firmware-package-for-samsung-sm883-mz7kh3t8hals.37154/

https://forums.servethehome.com/index.php?threads/pm863-fw-file.18084/

https://c.gmx.net/@324567863383819227/SlDWEtrmRueJ4nCqdGfOsQ/ROOT

I was attempting to wipe and reinstall MacOS X on an older Intel based Macbook by following this guide:

https://support.apple.com/en-us/102639

To begin this process, the directions have you press and hold Command-R.

The Disk Utility to wipe the computer was successful. However upon trying the next step to Reinstall macOS (in this case Sierra), it would result in the following error.

The Installer information on the recovery server is damaged.

Regardless of how many times I repeated the reinstall, it would always result in this error.

The root cause is due to the age of the laptop.  Internet Recovery was attempting to install a version of macOS that was originally shipped with the computer, but no longer existed on Apple servers.

Depending on the age of the computer, the solution may be found using this guide:

https://support.apple.com/guide/mac-help/use-macos-recovery-on-an-intel-based-mac-mchl338cf9a8/mac

What worked for me was the second option:

Option-Command-R: Start up from macOS Recovery over the internet. Use this key combination to reinstall macOS and upgrade to the latest version of macOS that’s compatible with your Mac.

This presented me with the option to Reinstall macOS Ventura, which was still available on Apple servers.

I was replacing a failed drive in an existing array in OMV.  After I connected a replacement disk, I went to Multiple Device -> Recover.

However the list of available drives for recovery was blank.  The next step I tried was to format the replacement drive under Storage -> Disk -> select the drive -> Wipe button.

Do you really want to wipe the device /dev/XXX ? All data will be lost.
I clicked Confirm.

At that point the GUI threw an error:

Connection Lost

500 – Internal Server Error
Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev –rereadpt ‘/dev/XXX’ 2>&1′ with exit code ‘1’: blockdev: ioctl error on BLKRRPART: Device or resource busy

In the notification area, an error was also logged:

Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev –rereadpt ‘/dev/XXX’ 2>&1′ with exit code ‘1’: blockdev: ioctl error on BLKRRPART: Device or resource busy

OMV\ExecException: Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; blockdev –rereadpt ‘/dev/XXX’ 2>&1′ with exit code ‘1’: blockdev: ioctl error on BLKRRPART: Device or resource busy in /usr/share/openmediavault/engined/rpc/diskmgmt.inc:295
Stack trace:
#0 /usr/share/php/openmediavault/rpc/serviceabstract.inc(622): Engined\Rpc\DiskMgmt->Engined\Rpc\{closure}()
#1 /usr/share/openmediavault/engined/rpc/diskmgmt.inc(227): OMV\Rpc\ServiceAbstract->execBgProc()
#2 [internal function]: Engined\Rpc\DiskMgmt->wipe()
#3 /usr/share/php/openmediavault/rpc/serviceabstract.inc(122): call_user_func_array()
#4 /usr/share/php/openmediavault/rpc/rpc.inc(86): OMV\Rpc\ServiceAbstract->callMethod()
#5 /usr/sbin/omv-engined(535): OMV\Rpc\Rpc::call()
#6 {main}

The reason for these errors is because the replacement disk had an existing superblock on it from another array.   When it was inserted into the OMV system, the system interpreted it as another array.  You can verify this by pulling up an OMV console and running the command:

cat /proc/mdstat

You should see listed your primary array marked as active, but also a second array marked as inactive and with only one device in it.  The device name will match the errors above and it represents the replacement drive.

Personalities : [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid1] [raid10]
mdXXX : inactive XXX[20](S)

Now if you go back to Multiple Deive -> Recover, the list of drives is no longer blank and the GUI presents you with the replacement drive. However, if you select the drive and click the Save button, the GUI will throw a new error:

500 – Internal Server Error
Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; mdadm –manage ‘/dev/mdXXX’ –add /dev/XXX 2>&1′ with exit code ‘1’: mdadm: Unknown keyword INACTIVE-ARRAY mdadm: Cannot open /dev/XXX: Device or resource busy

And in the notification area:

Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; mdadm –manage ‘/dev/mdXXX’ –add /dev/XXX 2>&1′ with exit code ‘1’: mdadm: Unknown keyword INACTIVE-ARRAY
mdadm: Cannot open /dev/XXX: Device or resource busy

OMV\ExecException: Failed to execute command ‘export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; export LANGUAGE=; mdadm –manage ‘/dev/mdXXX’ –add /dev/XXX 2>&1′ with exit code ‘1’: mdadm: Unknown keyword INACTIVE-ARRAY
mdadm: Cannot open /dev/XXX: Device or resource busy in /usr/share/php/openmediavault/system/process.inc:247
Stack trace:
#0 /usr/share/openmediavault/engined/rpc/mdmgmt.inc(419): OMV\System\Process->execute()
#1 [internal function]: Engined\Rpc\MdMgmt->add()
#2 /usr/share/php/openmediavault/rpc/serviceabstract.inc(122): call_user_func_array()
#3 /usr/share/php/openmediavault/rpc/rpc.inc(86): OMV\Rpc\ServiceAbstract->callMethod()
#4 /usr/sbin/omv-engined(535): OMV\Rpc\Rpc::call()
#5 {main}

You can see here the superblock on the replacement drive is causing an issue with the scripts due to the presence of an inactive array.

The solution is pretty straightforward:

1. Disconnect the replacement drive and wait for it to spin down.
2. Reattach it to OMV and wait for it to fully spin up.
3. Find it in the list of Disks
4. Use the GUI to perform a Wipe, either Quick or Secure.
5. The wipe should completely successfully
6. Navigate to Multiple Device and click Recover
7. Select your replacement Disk
8. Click Save to begin the recovery

At this point if you perform another scan of your arrays:

cat /proc/mdstat

You will still see the inactive array in the list. It wont cause any immediate problems to leave it, but you can flush it from the list by rebooting OMV.

When performing a manual apt-get upgrade command from the OMV CLI, I ran into this error when it tried to upgrade the grub-pc package.

grub-install: error: unable to identify a filesystem in hostdisk//dev/sdx; safety check can’t be performed.

where x is a device letter (e.g., sda, sdg, etc.)

The solution is pretty simple.

When presented with the Package configuration screen for grub-pc, there is the error:

GRUB failed to install to the following devices:

/dev/sdx

Do you want to continue anyway? If you do, your computer may not start up properly.

Writing GRUB to boot device failed – continue?

1. Choose the option for No.
2. Then find the correct boot device in the list and select it.  Double check that no other devices are selected.
3. Continue with the install

I was trying to perform a backup of the system C drive to another local storage D drive by using the Create a system image feature.  Each time the system image was attempted, it would result in the same error:

Windows Backup encountered an error when writing data to the backup target. (0x80780166)

Additional Information:
STATUS_WAIT_1 (0x80070001)

The system image had worked many times in the past, but it was now failing.   The only recent change to the system since then was upgrading the storage drive to a larger capacity and all the files had been migrated.

The solution was fairly simple.  I closed the Windows Backup tool and on the storage drive that had the previous backups, I found the folder titled WindowsImageBackup (located in the root of the drive).  I then renamed the folder (e.g., WindowsImageBackup-old).

When I attempted the backup again, it completed successfully.  Then I deleted the renamed folder to free up space.

This guide is how to resolve error 0x80070643 in Windows Update when trying to install an update related to the Windows Recovery Environment:

2024-01 Security Update for Windows 10 Version 22H2 for x64-based Systems (KB5034441).

The issue is related to either insufficient space in the existing recovery partition or the recovery partition does not exist at all as described in the below link. If you did a clean install of Windows 10, then the latter is likely the case.

https://answers.microsoft.com/en-us/windows/forum/all/install-error-0x80070643/ca8dc95f-bc48-427b-aa6a-3ef468f61ca0

You can resize an existing recovery partition or create a brand new recovery partition using the steps in this link:

https://support.microsoft.com/en-us/topic/kb5028997-instructions-to-manually-resize-your-partition-to-install-the-winre-update-400faa27-9343-461c-ada9-24c8229763bf

If you are creating a brand new recovery partition, then on step 8  which is to re-enable WinRE (reagentc /enable) you will receive this error:

REAGENTC.EXE: The Windows RE image was not found.

As described in the below link, this error is caused by a missing or corrupted Windows RE image file (Winre.wim) in the folder C:\Windows\System32\Recovery.

https://answers.microsoft.com/en-us/windows/forum/all/reagentc-does-not-let-me-enable-windows-re/dfa13429-0cd1-4bf9-83ae-92f1c8006132

To install a new Windows RE image, you will need to extract the file from a Windows 10 install disk or mounted ISO. If you don’t have an install disk or ISO, you can download one using the Media Creation Tool linked below:

https://www.microsoft.com/en-us/software-download/windows10

On older Windows 10 install disks, the source file we need (install.wim) that contains the Windows RE image is located at X:\x64\Sources. For .wim files you can use the free utility 7-Zip to extract what is needed (skip to Step 6 below).

However if you have a newer Windows 10 install image, such as 22H2, then the location and file described above no longer exist on the install disk.  The newer file (install.esd) is located at X:\Sources\.

If you find you have an .esd file, then it must first be converted to a .wim file using these steps, adapted from the link below.

How to Extract Install.ESD to Install.WIM (Windows 10/8)

Note that in order to complete these steps, you will need adequate free space on your local disk (roughly 2 times the size of the install disk).

1. Copy install.esd to a temporary location on your local drive.
2. Open an elevated Command Prompt with Administrator rights to the same temporary location.
3. Issue the following command to retrieve an index of available versions in the file.

   dism /Get-WimInfo /WimFile:install.esd

4. You should see an output similar to the following below. Review the list and make note of the index number that corresponds to your version of Windows 10 (e.g., 6 for Windows 10 Pro):Details for image : install.esdIndex : 1
   Name : Windows 10 Home
   Description : Windows 10 Home

   Index : 2
   Name : Windows 10 Home N
   Description : Windows 10 Home NIndex : 3
   Name : Windows 10 Home Single Language
   Description : Windows 10 Home Single Language
   
   Index : 4
   Name : Windows 10 Education
   Description : Windows 10 Education

   Index : 5
   Name : Windows 10 Education N
   Description : Windows 10 Education N

   Index : 6
   Name : Windows 10 Pro
   Description : Windows 10 Pro

   Index : 7
   Name : Windows 10 Pro N
   Description : Windows 10 Pro N

5. Now export the .wim file using the command below. Replace IndexNumber with the number noted earlier (e.g., 6 for Windows 10 Pro).

   dism /export-image /SourceImageFile:install.esd /SourceIndex:IndexNumber /DestinationImageFile:install.wim /Compress:max /CheckIntegrity
   

6. Once the export is complete, load 7-Zip file manager and navigate to the location of the newly created install.wim file.
   
   
7. Double click on install.wim to open the archive.
8. Inside you will see several folders. Navigate to the location:\Windows\System32\Recovery\ which contains Winre.wim 
9. Extract the Winre.wim file to your local Windows installation at the following location: C:\Windows\System32\Recovery

Before we can enable Windows RE, we must first set the location of the image file we just extracted as described in this link:

https://answers.microsoft.com/en-us/windows/forum/all/reagentc-does-not-let-me-enable-windows-re/dfa13429-0cd1-4bf9-83ae-92f1c8006132

1. Using an elevated Command Prompt, set the location of the file we just extracted:

   reagentc /setreimage /path C:\Windows\System32\Recovery

2. Now issue the command to enable Windows RE:

   reagentc /enable

3. You should be greeted with: REAGENTC.EXE: Operation Successful. You are now ready to retry the installation of Windows security update KB5034441
4. Remove/unmount any installation media, close 7-Zip File Manager and delete the files install.esd and install.wim.

I was looking to delete a specific restore point on a Windows 10 machine using the command line.  There are several guides available out on the web. For example:

https://www.majorgeeks.com/content/page/how_to_delete_some_or_all_system_restore_points_on_windows_10.html

https://softwarekeep.com/help-center/delete-windows-restore-points

Also the ofifical Microsoft guide:

https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/vssadmin-delete-shadows

You can also reference the built in help for vssadmin using the command line (e.g, type vssadmin delete shadows)

Delete Shadows /For=ForVolumeSpec [/Oldest] [/Quiet]
Delete Shadows /Shadow=ShadowId [/Quiet]
Delete Shadows /All
– For the given ForVolumeSpec deletes all matching shadow copies.
If /Oldest is given, the oldest shadow copy on the volume is deleted
If /All is given, then all shadow copies on all volumes that can be deleted will be deleted. If /Shadow=ShadowId is given, the shadow copy with that Shadow Copy ID will be deleted. Only shadow copies that have the ClientAccessible type can be deleted.
– The Shadow Copy ID can be obtained by using the List Shadows command. When entering a Shadow Copy ID, it must be in the following format:
{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}
where the X’s are hexadecimal characters. This ID can be obtained
through the List Shadows command.

Example Usage: vssadmin Delete Shadows /For=C: /Oldest

I was using the /Shadow=ShadowId option, but always received the error:

vssadmin delete shadows /shadow={aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee}

Error: Invalid option value.

What finally solved it for me was to NOT use PowerShell.  Using the identical command in Command Prompt was successful and you should be presented with:

Do you really want to delete 1 shadow copies (Y/N): [N]?

I was getting this error on Ubuntu 20.04 LTS with MySQL version 8.0.35.

Err:1 http://repo.mysql.com/apt/ubuntu focal InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B7B3B788A8D3785C

After some research, I tried several suggestions that I found at the links below, but they did not resolve the issue.

https://askubuntu.com/questions/1497140/how-to-fix-apt-update-after-to-upgrade-the-mysql-list-file

https://www.reddit.com/r/mysql/comments/18jj4hm/terminal_update_error/

https://askubuntu.com/questions/1389928/mysql-an-error-occurred-during-the-signature-verification

https://github.com/apache/airflow/issues/20911

However, finally came across this link which did have a solution:
https://askubuntu.com/questions/1498081/no-pubkey-and-some-of-the-file-has-an-unsupported-filetype

Below are the steps to quickly fix it:

1. Download an updated .deb file from the official mysql site:
   https://dev.mysql.com/downloads/repo/apt/
2. Install the deb (e.g., mysql-apt-config_0.8.29-1_all.deb):
   sudo dpkg -i <filename>
3. Then run apt-get update again and the error should not appear.

Some background: On a Windows 10 machine I had to recreate an existing user profile  due to some corruption. I followed this guide (except for the step related to ProfileGuid in the registry, since it does not exist in Windows 10):

https://community.spiceworks.com/how_to/121165-re-create-user-profile-windows

Everything worked great and I was able to log on. However I quickly realized none of the built in Windows Apps worked.  They would open and then very quickly close without any error message window.

Each of these apps could be fixed quite easily using the Start Menu -> type: Apps -> launch Apps & features.  Find the problematic app, click Advanced options. First choose the Terminate button. Then choose the Reset button. The app then worked without crashing instantly.

However this same issue occurred with Microsoft Store, but that app unfortuantely is not in the Apps & features list.

Event viewer did have information for these crashes. For example

Faulting application name: WinStore.App.ex
Faulting module name: KERNELBASE.dll, version: 10.0.19041.3758
Exception code: 0xc000027b
Fault offset: 0x000000000012db22
Faulting application start time: 0x01da427eb19954ed
Faulting application path: C:\Program Files\WindowsApps\Microsoft.WindowsStore_22311.1401.2.0_x64__8wekyb3d8bbwe\WinStore.App.exe
Faulting module path: C:\Windows\System32\KERNELBASE.dll
Faulting package full name: Microsoft.WindowsStore_22311.1401.2.0_x64__8wekyb3d8bbwe
Faulting package-relative application ID: App

I tried to reset Microsoft Store using Start menu -> type: wsreset utility.  However that failed and would generate the error -2147219196 related to PurgeCaches.

I also tried uninstalling and reinstalling Microsoft Store via PowerShell.  Each of these was successful but didn’t fix the problem.

Finally I stumbled on this article:

Microsoft Store missing in Apps & Feature – Microsoft Community

This helped me resolved the issue and you can follow these quick steps:

1. Uninstall Microsoft Store using PowerShell (admin):

   get-appxpackage *WindowsStore* | remove-appxpackage

2. Start Menu -> type: Apps -> launch Apps & features
3. Uninstall Xbox app
4. Uninstall Xbox Live app
5. Reinstall Xbox app via this link https://aka.ms/XboxInstaller
6. Launch Xbox app
7. At the top you should see a notification that Microsoft Store is needed.
8. Click it to install Microsoft Store using the Xbox App
9. Once complete, Microsoft Store should now be functional!