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Windows 7: Microsoft Update changed drive letters and Win 7 won't start

14 May 2011   #1

Windows 7 64 bit (Home edition I think)
Microsoft Update changed drive letters and Win 7 won't start


When my pc restarted after a windows update (Windows 7 64 bit), Windows 7 would not restart. The auto repair utility was unable to make repairs although I am able to use it to get to DOS and see my drives, folders, files etc.

It seems like the C: drive (solid state 58gb) is now named the D: drive and the former D: drive (500gb internal) is now named C:

The problem signature states:
Problem Event Name: StartupRepairOffline
Problem Signature 01 and 02: 6.1.7600.16385

I have been able to put in a bootable AVG disk and scan the drive for viruses (none found), but when I put in a Bart disk, I get the BSOD.

I also found a link showing how to set the disk partition to active for the 58gb solid state boot drive, but still could not auto repair.

Any suggestions are welcome. The repair factility can't find recover points (probably because it can't find the operating system).


My System SpecsSystem Spec
15 May 2011   #2

Microsoft Community Contributor Award Recipient


Remove the 500gb HD, than do the Startup Repair.

Startup Repair
Note: You may need to do startup repair 3 to 4 times.
Startup Repair - Run 3 Separate Times
My System SpecsSystem Spec
16 May 2011   #3


Make sure WIn7 System Reserved boot partition (if you have it) or the Win7 partition itself if marked Active before running the repairs, with the other HD's removed as Theog says.
My System SpecsSystem Spec


 Microsoft Update changed drive letters and Win 7 won't start

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