Let’s say you have a Hyper-V guest operating system that is running Windows Server or Windows 11/10, and it has a disk that is connected to a SCSI controller. Now, if you receive an error Unexpected failure. Error code: [email protected], then this article may help you.

Unexpected failure, Error code [email protected]

You might see this error message in the Event Viewer.

There is a KB979391 that ONLY explains why this happens, but no actual fix is mentioned in that article. It’s been reported in a few forums, that issue can be resolved by reinstalling your Virtual drive software like Alcohol 120%, DAEMON Tools Lite, etc.

One thing you have to remember is after you remove the software, there is a good chance that it may leave the SPTD.sys driver behind. This driver is notorious on Windows 7 for causing frequent crashes including the Blue Screens.

There is an uninstaller tool that’s available that will help you in removing it. Download the application from here. Run the application, then click on Uninstall to remove it.

Reboot your computer to take effect.

Alternatively, you can go to use the registry method to disable it:

Go to Start under search type in Regedit

Then go to:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\ Services\sptd

In the right-side panel, you’ll have to set the DWORD Start value to 4 and reboot the machine once.

I hope this helps someone.