[OBSOLETE] Unofficial workaround for Snapman.sys BSOD Windows safe mode
ATIH 2016 b5518
Hello everyone,
I spend some brain into the BSOD problem with snapman.sys that prevented to start Windows in safe mode.
references:
https://forum.acronis.com/de/node/96768
https://forum.acronis.com/de/node/96465
I want to share an unofficial solution.
Please be aware that this solution is not yet proven / supported by Acronis.
Affected product:
Acronis True Image Home 2016 build 5518
Tested with:
Windows 10 pro 64bit (release build 10240)
Not tested but expected to be compatible:
all Windows versions
Problem:
BSOD
System_Thread_Exception_Not_Handled when trying to start Windows in Safe Mode.
Caused by snapman.sys
Workaround:Altering registry entry ImagePath under [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\snapman]
Altering registy key DWORD "Start" to value 4 (HEX)
As pointed out in one of the threads I have noticed that the path to the snapman.sys is missing the %systemroot% variable. This is commonly present in other driver entries that will be loaded by the Windows Kernel at boot time, however I've also noticed that it is not included in all of those drivers located in the Windows registry.
What I can say now is that adding the %systemroot% to the ImagePath string does fix the issue.
The BSOD in safe mode came up reproducibly as soon I reverted that string to the Acronis default without the %systemroot% variable. (original entry is: system32\drivers\snapman.sys)
Based on my knowledge about Windows, this solution should also work for other 64bit versions of Windows, so Windows 7 and 8.x but I have not tested this.
Furthermore I haven't tested the behaviour for any 32bit version of Windows and advise not to use the workaround on a 32bit Windows installation. Don't apply the hotfix if you are not sure what you're doing and don't apply it on Windows versions at all that haven't been tested.
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issue fixed in in build 5576, as far I have monitored the registry key the update to the mentioned build will revert all changes to default,
so basically the Imagepath and Start DWORD is set as nothing was ever changed.
Please check if you still have the BSOD when starting in safe mode after the upgrade. I cannot reproduce it anymore.
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hi Karl:
I now have the same problem (BSOD in safe mode or normal mode caused by snapman.sys) . But I wonder how to modify the registy key because I can not enter the OS normally.
thank you!
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You can remove the snapman service using WinPE recovery media. See the attached file for detailed instructions.
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406647-137218.docx | 13.33 KB |
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hi Mustang:
really appreciate your help, thank you !
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You're welcome. Let us know if you get your system back.
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Hi Mustang:
thanks
I tried to follow the steps to repair my system. But I can not find the "snapman" in
UpperFilters of HKEY_LOCAL_MACHINE\REMOTE_STSTEM\ControlSet001\Control\Class\{4d36e967-e325-11ce-bfc1-08002be10318
&
HKEY_LOCAL_MACHINE\REMOTE_STSTEM\ControlSet001\Control\Class\{71a27cdd-812a-11d0-bec7-08002be2092f.
Are the two steps necessary for repairing? Can I skip the two steps ?
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You only need to remove the snapman UpperFilter if it is present. You should only need to delete the snapnam servive to make the system bootable.
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hi Mustang:
I want to give you a big hug. My system is back. thank you !!!!!!!!
^_____________^
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Great to hear.
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