Many users have started experiencing random crashing of explorer and msiexec.exe when trying to start Windows Update or install anything that uses an MSI based installer. This issue is bad enough that some people have even formatted because of it, only to have it come back again.
Rafael has discovered that the fault lies with the SQM Client which is part of the Customer Experience Improvement Program. It seems that ANY process that calls WinSqmStartSession in ntdll.dll will start crashing when MachineThrottling is enabled in the registry, which seems to happen as a result of CEIP running.
Use the following to fix the issue.
1. Open a Command Prompt as Administrator
2. Type reg delete HKLM\SOFTWARE\Microsoft\SQMClient\Windows\DisabledSessions /va /f and press enter.
3. That’s it, no further action is necessary
Source: http://chris123nt.com/2009/01/18/sqm-cl ... windows-7/
SQM Client Causing Crashing in Windows 7
SQM Client Causing Crashing in Windows 7
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