Windows 10 guest gives error on starting after upgrading virtualbox

[DJSuson]

I recently upgraded my Slackware Linux host system, which included upgrading virtualbox from version 6.1.28 to 6.1.34. The installation completed without any problems and I was able to import all of my Windows guests without a problem. The Windows XP and Windows 7 guests started without incident, but the Windows 10 guest immediately went to a blue screen saying that the PC ran into a problem and needs to restart. It continues to loop through this until I turn off the virtual machine. I've had a similar problem with my Windows 10 guest at work after upgrading my work system the same way. I dimly remember there being a problem with Windows 10 and a hardware key, but I don't remember the details or solution. Can anyone give me guidance on how to get these guests working again?

[scottgus1]

I dimly remember there being a problem with Windows 10 and a hardware key

If the VM's "hardware key" (the UUID) changes, the VM OS should only ask for reactivation, not fail to boot.

I recently upgraded my Slackware Linux host system, ... I was able to import all of my Windows guests without a problem.

Importing is not necessary when the host OS is upgraded. Importing may change the UUIDs, see above. A full folder-copy backup of the VM folders will keep the existing UUIDs, and using the Virtualbox main window's Machine menu Add command will bring the VMs back in.

the Windows 10 guest immediately went to a blue screen saying that the PC ran into a problem and needs to restart. It continues to loop through this...

This shows a VM "hardware" that is still apparently running ok and the VM OS having the issue.

Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.

Right-click the VM in the main Virtualbox window's VM list, choose Show in Explorer/Finder/File Manager. In the "Logs" subfolder, zip the VM's "vbox.log", and post the zip file, using the forum's Upload Attachment tab. (Configure your host OS to show all extensions so you can find the "vbox.log", not "vbox.log.1", etc.)