Unable to reboot guest Windows 7 after 6.1 upgrade

[AnrDaemon]

I've recently upgraded my VirtualBox to 6.1 and while going GA upgrade on my Windows VM, I noticed a strange behavior.
I can run and stop (from ACPI signal or from OS menu) the machine just fine, but doing a reboot will always cause VM to crash.
I'd appreciate some hints, if possible.

[scottgus1]

The hardening log shows an ExitCode of 0xc0000005. See Diagnosing VirtualBox Hardening Issues.

NTDLL.dll appears hacked:

5b50.5944: ntdll.dll: Differences in section #1 (.text) between file and memory:

Fraps appears to have lost its authenticity certificate

5b44.5668: supR3HardNtViCallWinVerifyTrust: WinVerifyTrust failed with 0x800b0101 (CERT_E_EXPIRED) on '\Device\HarddiskVolume3\Programs\Fraps\fraps64.dll'
5718.5b5c: Error (rc=-5629):
5718.5b5c: RTLdrGetBits failed on image acgenral.dll: Unknown Status -610 (0xfffffd9e)

The NVidia WDDM D3D driver appears to be disliked, see further down, too:

5b44.5c40: Error (rc=0):
5b44.5c40: supR3HardenedScreenImage/LdrLoadDll: rc=Unknown Status -23303 (0xffffa4f9) fImage=1 fProtect=0x0 fAccess=0x0 \Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll: WinVerifyTrust failed with hrc=CERT_E_CHAINING on '\Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll'

The vbox.log reports a crash while resetting and enumerating 3D capabilities:

01:39:28.098578 Changing the VM state from 'RUNNING' to 'RESETTING'
..............
01:39:28.100025 VMSVGA3d: cap[29]=0x00000000 {MAX_VERTEX_SHADER_TEMPS}
01:39:28.100025 VMSVGA3d: cap[30]=0x00000000 {MAX_FRAGMENT_SHADER_TEMPS}
01:39:28.100026 VMSVGA3d: cap[31]=0x00000000 {TEXTURE_OPS}
01:39:28.100697 
01:39:28.100698 !!! rtR3WinUnhandledXcptFilter caught an exception on thread 0000000000005c40!!!

And the on-the-fly hardening apparently doesn't like the NVidia WDDM D3D driver:

00:00:06.443469 supR3HardenedErrorV: supR3HardenedScreenImage/LdrLoadDll: rc=VERR_CR_PKCS7_KEY_USAGE_MISMATCH fImage=1 fProtect=0x0 fAccess=0x0 \Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll: WinVerifyTrust failed with hrc=CERT_E_CHAINING on '\Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll'
00:00:06.443609 supR3HardenedErrorV: supR3HardenedMonitor_LdrLoadDll: rejecting 'C:\Windows\system32\nvd3dumx.dll': rcNt=0xc0000190
00:00:06.443923 supR3HardenedErrorV: supR3HardenedScreenImage/NtCreateSection: cached rc=VERR_CR_PKCS7_KEY_USAGE_MISMATCH fImage=1 fProtect=0x2 fAccess=0x7 cHits=1 \Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll
00:00:06.444202 supR3HardenedErrorV: supR3HardenedScreenImage/NtCreateSection: cached rc=VERR_CR_PKCS7_KEY_USAGE_MISMATCH fImage=1 fProtect=0x2 fAccess=0x7 cHits=2 \Device\HarddiskVolume3\Windows\System32\nvd3dumx.dll

I can't see anything else, and those logs are somewhat hard to decipher so all of the above may be moot. If you go back to the previous working Virtualbox version, does the guest return to stable reboots?

Also, per the 'diagnosing' tutorial, if you start the guest headless or detachable, can you reboot stably on the present 6.1.2?

[AnrDaemon]

Ok, this is guest additions. Once I upgraded GA in another machine (had 4.3, installed 6.1.4), it started crashing just the same way.

[AnrDaemon]

Turned off 3D acceleration (which does not work either way with new GPU emulation), crash disappeared.

[AnrDaemon]

Updated video drivers. Enabled 3D acceleration back. Rebooted a few times just fine, Aero effects are back, though screen updates are not very reliable. There's still black patches appear every now and then.