I work as the IT manager for a small non-profit in Ireland that reuses computers for education and we recently had to deal with the following strange issue.
After installing the windows update KB3177467 on windows 7 the operating system is no longer recognised and the system goes in a repair boot loop. System recovery starts, automatic repair cannot recognise the existence of the windows operating system, it fails to fix the issue and reboots back into recovery.
We had reports from our school clients for more than 100 computers so far with the same issue and we expect many more.
To the best of my ability and understanding of windows, I came up with the following step by step guide that resolved the issue for us. The process basically is recovering windows by rebuilding windows BCD, replacing the file that fails signature verification with the new BCD, booting in windows and verifying all system files.
- Start windows recovery (inevitable at this stage of the issue as it starts by default)
- When automatic repair starts press cancel as quickly as possible
- Select “view advanced options for system recovery and support”
- Select keyboard layout (UK or US will be ok)
- Select a local admin user and log in with the user’s password
- Open a terminal by clicking on command prompt
- Allow edits to existing windows BCD by fixing the file attributes: attrib c:boot\bcd -h -r -s
- Rename the old BCD: ren c:boot\bcd bcd.old
- Rebuild windows BCD with the bootrec command: bootrec /rebuildbcd
- Once bootrec recognises the existing windows OS on the hard drive type “Y” and press enter to confirm the creation of the new BCD
- Once the new BCD is created successfully you will receive the message “The operation completed successfully”
- Knowing that the system will fail to verify the file C:\Windows\System32\winload.exe you can proceed with replacing it with the files from the recovery partition
Backup the old winload.exe file by typing the following commands:
ren d:windows\system32\winload.efi winload.efi.bak
ren d:windows\system32\winload.exe winload.exe.bak
- Copy the original recovery files from the recovery partition to the system32 folder by following these commands (successful completion returns the message “1 file(s) copied”):
copy winload.exe d:windows\system32\
copy winload.efi d:windows\system32\
I hope this guide helps some people deal with this strange issue. Hopefully an official reply from Microsoft will be available soon as to why so many people are having various different problems with this specific update and ideally resolve this.