Solved Win 8.1 UEFI won't boot after modifying GPT partitions

[passerby8]

Hello Windows experts.

I've been using Windows very little these past years and now I bought a laptop that is very 8.1 friendly and I'm clueless. I need your help.

I first wiped everything off the disk and installed other systems (GNU/Linux). Then I installed Windows 8.1 Single Language 64 bits alongside my other OS. Installation was fine and they lived together happily. Until one day Windows stopped booting. I'm not sure why, but I believe it has to do with modifying other GPT partitions (erasing/creating) which in turn weren't related to Windows at all (ext4 partitions). I used to do this with previous Windows versions installed in other computers and there was no problems, but I guess Windows got very "touchy" (pun intended) and doesn't like this anymore.

Now Windows boots but resets and then enters in the recovery mode. So I tried the repair options, and I also tried with the installation disk I created with media creation tool, but no joy. Everything fails. The log file at C:\Windows\System32\Logfiles\Srt\SrtTrail.txt mentions only 0x0 and 0x490 as errors. But that doesn't say anything to me (I hope it does to you).

So it doesn't boot through, but I can access the troubleshooting options. That's all.

I hope this isn't too serious and you can point me in the right direction to fix this baby soon without re-installing Windows.

Thanks in advance! :thumb:

PS: Secure boot and Fast boot were always disabled and the system has also always been working in UEFI mode.

 

[passerby8]

Solved it !

Got it!

Deep searching the web I found my answer.

It was simple and dumb, I can't believe all the automated recovery/repairing processes couldn't solve this!

It turns out that Win messed up the drive letters. What should be C was instead E.

This post was my key!

Based on it, this is the procedure I followed:

Get into the command prompt (either from a recovery disk, installation disk, or the menu that comes up after Windows tries to Diagnose, Recovery, etc).

Don't even bother with the automated recovery process, it will not work as it cannot find a Windows partition.

Once in the command prompt, type:

DISKPART (Enter)

In case you only have one drive, then:

DISKPART> sel disk 0 (Enter)

DISKPART> list vol (Enter)

And take a look here, pay attention to what is the letter assigned to the Windows root (main) partition. Now make it match with the letter it had prior the mess up. Assuming your root partition is vol 3, and that it had the letter C:, this is (basically) what you should do:

DISKPART> sel vol 3 (Enter)

DISKPART> assign letter=C: (Enter)

DISKPART> exit (Enter)

Now close the command prompt and continue with the Windows booting process.

Hope this helps somebody else! (I love this pink elephant, it's so irreverent!)

 

[blueelvis]

Hi Passerby8 ^_^,

Thanks a lot for posting the solution which worked for you. I am sure this would help the future visitors.

Let us know in case of any further problems ^_^


-Pranav