BSOD starting Windows 7 Guest

[PeteOnSpeed]

Host: Windows 10 Pro x64 Version 1909
VirtualBox: 6.1.4
Guest: Windows 7 x68

Symptom: BSOD on Boot of Windows Guest. Worked before with same configuration. Works also on second Notebook with same configuration?!

I've tried all settings, reinstalled 6.1.2 (did not help) and then 6.1.4 again
I've run out of ideas - please help!

Thank you, Pete

[scottgus1]

The hardening log shows that your video drivers might need an update (the drivers aren't signed right).

Also there's a very strange file that reports itself in 8.3 naming: 'C:\PROGRA~2\WS-BOO~1\ASSIST~2.DLL'

See Diagnosing VirtualBox Hardening Issues

I don't see evidence of a BSOD in the posted log. Are you using that term to refer to Virtualbox not starting the guest and putting up an hardening error box instead?

[PeteOnSpeed]

yes - the BSOD happens to the win7 guest. Sometimes I also get a segmentation fault from VB.
Yesterday I installed an older Nvidia driver and the Error 0xC0000005 in the hardening log disappeard, but not the BSOD.
So I have to search for something else...

Thank you!