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Windows 7: BSOD on boot - Drive letters switched - Windows on G:

15 May 2015   #1

Windows 7 Enterprise x64
BSOD on boot - Drive letters switched - Windows on G:

Last night when I went Start menu > Shut down, I got a BSOD. Because it was late and I occasionally get a BSOD without further issues, I just left it.

This morning I find that everytime Windows attempts to boot, it gets just past the startup splash screen, and then another BSOD. "Startup repair cannot repair this computer automatically".

Problem signature:
Problem event name: StartupRepairOffline
Problem Signature 01: 6.1.7600.16385
Problem Sig 02: 6.1.7600.16385
Problem Sig 03: unknown
Prob Sig 04: 21201115
Sig 05: AutoFailover
Sig 06: 11
Sig 07: CorruptFile
OS Version: 6.1.7600.
Locale ID: 1033
The strangest and I hope most telling and significant part is that the drive letters for my stuff are all switched around. Originally I was set up as:
C:\ - Windows OS
D:\ - System Reserved (I assume)
E:\ - Temp drive partition
F:\ - Data1
G:\ - Data2

Now, it seems that windows has been reassigned to G:
C:\ - Temp
D:\ - System Reserved
E:\ - Data2
F:\ - Data1
G:\ - Windows OS

I have tried to use diskpart to reassign the drive letters back how they were. I was able to do this from the command line, but after rebooting, I get another BSOD and the drive letters revert to this messed up order.

I took a picture of the BSOD code and got:
STOP: 0x000000F4 (0x00...003, 0xFFFFFAB00C0***fuzzy**,0xFFFFF80003779E20) -I think
This page: Troubleshooting Windows STOP Messages led me here:;en-us;330100 which kind of makes sense if windows is now on a G: drive??

I also tried this: Bootrec.exe Tool - How to Use in Windows Recovery Environment
with no luck, I get "file not found" for bcd.

The Startup Repair also gives these error codes:
Root cause found:
Unknown Bugcheck: Bugcheck f4. Parameters = 0x3, 0xfffffa800be76b10, 0xfffffa800be76df0, 0xfffff800037cce20.

Repair action: System files integrity check and repair
Result: Failed. Error code = 0x490
Time taken = 266045 ms
I can't run the DM Log Collector because I can't boot into windows (I'm troubleshooting and posting on a macbook).

I can't think of any recent hardware or software changes, although I did get a system update two nights ago I think.

Thank you so much for any insight. I do have backups and am willing to do a restore or fresh install, but it would be good to know if this is hardware, software, malware, or a freak accident. I also kinda wanted to wait until Win 10 came out before doing a new install. *sigh*

My System SpecsSystem Spec
15 May 2015   #2

Windows 7 Enterprise x64

A couple other details as I continue to look around:
1) chkdsk G: \f says "Windows has checked the file system and found no problems" though G doesn't have a volume label and it also says "Failed to transfer logged messages to the event log with status 50."
2) My SSD C: drive that had windows on it was very close to full when the problem started, not sure if that's a factor (should have had 2-3GB free space still).
My System SpecsSystem Spec
15 May 2015   #3

Windows 7 Enterprise x64

I have a Macrium Reflect Rescue CD that I booted from.
It has a fix boot problems wizard, and it found Windows on the C: as it should be. When it came time to "select which partition your PC should boot from", it showed two partitions on my OS SSD: <No Name> (C: ) and System Reserved (K: ) -why K??
It had K automatically selected, but I chose C: instead and finished the wizard which did several things: (Reset the boot disk ID, Replace MBR, Replace partition sector boot code, Rebuild BCD and Boot.ini). After rebooting, I got the same BSOD, but instead of the Startup Repair after the second reboot, I got options for Safe Modes for the first time. I chose Safe Mode with Command Prompt and got a BSOD. I tried Last Known Good Configuration as well and got the same BSOD.
My System SpecsSystem Spec

15 May 2015   #4

Windows 7 Enterprise x64

I was just about to do a restore from an OS image I made a few months ago (relatively small loss if all goes smoothly), when I noticed something odd. The OS image holds two partitions:
System Reserved (no letter) NTFS Active, and <No label> (C: ) NTFS Primary

whereas the current situation is:
System Reserved (G: -wait, now this one is G???) NTFS Primary, and <No label> (C: -at least this is C now) NTFS Active.

From what I've been reading, the System Reserved should have no letter and should be the Active partition, not the C partition. I will attempt to fix this with diskpart and see what happens: Partition - Mark as Active
My System SpecsSystem Spec
15 May 2015   #5

Windows 7 Enterprise x64

So my best effort to this point has been to set System Reserved as Active (no letter), C: as Primary, other drives as they were, use the Macrium Fix Boot Problems tool with the System Reserved selected (instead of C: as I did last time) and then reboot. No luck. With Macrium, at least failing to boot, it keeps the drive info I've changed, with the exception that it keeps giving the System Reserved a letter and so my Data2 keeps getting bumped down the list. I'm going to try a restore from my OS image now.

Apologies for spamming this thread, but I feel it's important to document my process and keep the info current in case anyone wants to jump in.
My System SpecsSystem Spec
15 May 2015   #6

Windows 7 Enterprise x64

Well... the OS restore from my backup seems to have worked. I'm a bit hesitant to install the latest Win 7 updates. Seems that hardware wasn't the issue.
My System SpecsSystem Spec

 BSOD on boot - Drive letters switched - Windows on G:

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