Bugcheck 0x51 REGISTRY_ERROR help needed

Question

Hi there.

After manualy installing .Net Framework 4.8 Developer Pack I'm experiencing unstable system behaviour. Windows did crash every 5-10 minutes while on idle. The brief crash dump analysis shows the root cause of a crash:

NGEN.exe 

Somehow it has managed to crash system during deleting of some registry key (still unable to figure out exact key by myself cuz lack of windbg and dump analysis knowledge) by HvFreeCellHint - NtDeleteKey functions.

When I did uninstall of .Net Framework update and revert to 4.7.2 ngen (32-bit) was unable to execute its tasks every time throwing CATASTROPHIC FAILURE (E_UNEXPECTED). 

Didn't have a restore point already. So, can you tell me, how to restore normal state of OS and .NET in particular without doing completely system rebuild?

Dump url: https://1drv.ms/u/s!AhdjYi359YDTgug4pZFZ7CSCvvTgdw?e=4RHdE3

Additional files: https://1drv.ms/u/s!AhdjYi359YDTgug5mNUoreiQ2oS01w?e=7ix0nJ

Answer 1

You have no restore points, but you have dome something to the OS and you want to get it back to normal without doing a clean install.

@@@@@@@@@@@@@@@@@@@@@@@@

Each Method/step below progresses to the next if the first does not fix any corrupted files that are found, etc.

Have you read this Microsoft information about repairing corrupt system files and errors?

"Use the System File Checker tool to repair missing or corrupted system files"

https://support.microsoft.com/en-us/kb/929833

_________________________________________________

And these eightforums.com Tutorials are very detailed for problems resulting from SFC Scan:

"How to Run "SFC /SCANNOW" Command at Boot or in Windows 8 and 8.1"

http://www.eightforums.com/tutorials/3047-sfc-scannow-command-run-windows-8-a.html

Read this Section there in conjunction with the rest of the information they give in above link.

   Note

If SFC could not fix something, then run the command again to see if it may be able to the next time. Sometimes it may take running the sfc /scannow command 3 times restarting the PC after each time to completely fix everything that it's able to.

If not, then run the **Dism /Online /Cleanup-Image /RestoreHealth**command to repair any component store corruption,

Repair-WindowsImage -Online -CheckHealthRepair-WindowsImage -Online -ScanHealthRepair-WindowsImage -Online -RestoreHealth

Restart the PC afterwards, and try the sfc /scannow command again.

If still not, then try using OPTION ONE above to run the sfc /scannow command at boot

If still not, then you could do a refresh of Windows 8, or run a System Restore using a restore point dated before the bad file occured to fix it. You may need to repeat doing a System Restore until you find a older restore point that may work.

If still not, then you can use the steps in the TIP box in the OPTION THREE section to manually replace the files that SFC could not fix.

__________________________________________________

"How to Refresh Windows 8 and Windows 8.1"

http://www.eightforums.com/tutorials/2293-refresh-windows-8-a.html

Refreshing your PC goes like this:

• The PC boots into Windows RE (RecoveryEnvironment).
• Windows RE scans the hard drive for your data, settings, and apps, and puts them aside (on the same drive).
• Windows RE installs a fresh copy of Windows.
• Windows RE restores the data, settings, and apps it has set aside into the newly installed copy of Windows.
• The PC restarts into the newly installed copy of Windows.

_________________________________________________

I've scanned my system with system file checker and dism but both didn't report any significant errors. So I assume only OPTION THREE is valid now.

After some time digging with ProcessMonitor I've found the root cause of this creepy ngen behaviour. Registry key HKLM\Software\Wow6432Node\Microsoft.NETFramework\v2.0.50727\NGenService\Roots has been corrupted. It contains keys which are not normally processed by regedit tool but ngen still enumerates values from them:

Do you know any good implementation of registry reader/writer which doesn't relly on registry win32 api or I need manually navigate through registry HBINS trying to fix them?

Answer 2

You have no restore points, but you have dome something to the OS and you want to get it back to normal without doing a clean install.

@@@@@@@@@@@@@@@@@@@@@@@@

Each Method/step below progresses to the next if the first does not fix any corrupted files that are found, etc.

Have you read this Microsoft information about repairing corrupt system files and errors?

"Use the System File Checker tool to repair missing or corrupted system files"

https://support.microsoft.com/en-us/kb/929833

_________________________________________________

And these eightforums.com Tutorials are very detailed for problems resulting from SFC Scan:

"How to Run "SFC /SCANNOW" Command at Boot or in Windows 8 and 8.1"

http://www.eightforums.com/tutorials/3047-sfc-scannow-command-run-windows-8-a.html

Read this Section there in conjunction with the rest of the information they give in above link.

   Note

If SFC could not fix something, then run the command again to see if it may be able to the next time. Sometimes it may take running the sfc /scannow command 3 times restarting the PC after each time to completely fix everything that it's able to.

If not, then run the **Dism /Online /Cleanup-Image /RestoreHealth**command to repair any component store corruption,

Repair-WindowsImage -Online -CheckHealthRepair-WindowsImage -Online -ScanHealthRepair-WindowsImage -Online -RestoreHealth

Restart the PC afterwards, and try the sfc /scannow command again.

If still not, then try using OPTION ONE above to run the sfc /scannow command at boot

If still not, then you could do a refresh of Windows 8, or run a System Restore using a restore point dated before the bad file occured to fix it. You may need to repeat doing a System Restore until you find a older restore point that may work.

If still not, then you can use the steps in the TIP box in the OPTION THREE section to manually replace the files that SFC could not fix.

__________________________________________________

"How to Refresh Windows 8 and Windows 8.1"

http://www.eightforums.com/tutorials/2293-refresh-windows-8-a.html

Refreshing your PC goes like this:

• The PC boots into Windows RE (RecoveryEnvironment).
• Windows RE scans the hard drive for your data, settings, and apps, and puts them aside (on the same drive).
• Windows RE installs a fresh copy of Windows.
• Windows RE restores the data, settings, and apps it has set aside into the newly installed copy of Windows.
• The PC restarts into the newly installed copy of Windows.

_________________________________________________

Answer 3

Thanks Bill for your reply.

I did this step when I was recovering my system from BSOD. Completely uninstalled 4.8 SDK, Targeting Pack and Update that install .NET Framework 4.8. BSOD gone but 32-bit ngen unable to do anything with native image cache. Any commands like:

 * ngen display

 * ngen update

 * ngen executequeueditems (eqi)

doesn't work anymore.

I think that Native Image cache is in kind of broken state and I don't know how to restore/rebuild it, ngen update /force doesn't work too.

PS Installation of .NET Framework 4.8 is not blocked. I can normally install it but I don't want to cuz BSOD will return.

Answer 4

https://docs.microsoft.com/en-us/dotnet/framework/install/troubleshoot-blocked-installations-and-uninstallations

To uninstall .NET Framework 4.5.x/4.6.x/4.7.x/4.8 from your computer, go to Control Panel, choose Programs and Features, choose View installed updates, select Update for Microsoft Windows (KB2828152) and then choose Uninstall.Apr 17, 2019