Fixing Windows Boot Files using Command Prompt

[Danny Bateman]

Hey all,

 

Came home last night to an unbootable rig. Sucks because I had just done a Windows reset that seemed to work well to iron out recurring hanging when using browsers. Plus the GF and I had just started Portal 2 on our Steam Link the night before...

 

Anyway, I'm getting some help from a guy at Tom's Hardware (good utility for problems, BTW) but we keep hitting roadblocks.

Apparently the SSD Windows is installed on lacks a bootloader partition? This is news to me. Anyway, he was going to have me create one from scratch.

I get error 0xc000000f saying I've got an error in \Boot\BCD when trying to boot normally, so I'm booting from the W10 recovery disk I recently made. Already tried bootrec /fixMBR and /fixboot (both worked) but bootrec /rebuildBCD fails telling me the requested system device cannot be found.

 

Here are his instructions for Command Prompt:

 

diskpart
select disk 0
select partition 1
shrink desired=500
create partition primary
format fs=ntfs quick
active
assign letter=g
exit
bcdboot c:\windows /s g:

 

Problem is when I go to shrink the partition (shrink desired=500), I get the following message:

 

The specified shrink size is too big and will cause the volume to be smaller than the minimum volume size.

 

Any ideas? I figured there were at least a few of you who work on computers and are way more well-versed in this stuff than I am. Thanks in advance!

[Lil' Red]

You might try running the system file checker utility to try and repair any corrupted or missing boot files if you haven't yet. Here are instructions on how to do that from a recovery cd. I don't have any ideas on how to fix the shrink size error you are receiving though.

[Danny Bateman]

Ok. tried sfc on both drives. Both had no integrity violations.

 

But still no boot. He actually had me delete my second partition on OS disk and recreate it. This seems to have backfired because now I no longer get my 0xc000000f error message but it simply tells me there is no Windows on my computer.

 

I'm thinking a fresh install of Windows would be best. But upon trying that, I get this message:

 

 

I found two possible solutions online. One said to disable EFI boot sources from within BIOS. But my Win10 disc is listed as UEFI so I'm not sure that's a good idea?

The other one is to simply delete the partitions on the screen above and create a new (GPT) one to reinstall Windows. I realize that would lose whatever files are on C:, but I'm OK with that.

 

Which do you think is a better solution, if either of them?

[Lil' Red]

I believe both solutions should work. The first solution would only require temporarily disabling EFI boot sources to install windows and then reenabling it after it is installed so the fact that it uses UEFI shouldn't be an issue. If it were me, I'd probably try that solution first since it would preserve your files.

[zoogs]

Hm. To pull files off it, I'd try a Ubuntu LiveCD or something like that -- boot up from the CD, access your hard drive, transfer everything you need to off there. I don't think you should have to lose the files on C:\ so I'd give this a try before deleting anything.

 

For your fresh install of windows, I *think*? (Don't quote or rely on me!) that message is because you already have windows installed on that partition (hence the MBR?) If you install windows on a partition with Windows already installed, wouldn't you lose everything anyway?

[Danny Bateman]

Update:

Got things working again. Did end up having to wipe that drive and do a fresh install. Don't think I lost anything too important, aside from maybe a big backlog of photos that I should've had backed up anyway. I may have a full backup of that drive online anyway... I'll have to do some searching to find out. It's working just fine now though. I was afraid when it happened that the drive was failing, which would have been unfortunate because I just replaced that SSD a couple years back.

 

More than anything, I'm just perplexed as to why it happened. I had just done a Windows reset, keeping my files, a few days prior due to some serious unexplained hanging issues. It was happening across multiple browsers (Edge, Firefox, Chrome) when browsing to the point that I couldn't even get to the Task Manager Ctrl+Alt+Delete screen until the hanging resolved itself a minute or two later. I do have a horrible habit of having too many tabs open and too many programs in general, but I've got 8 GB RAM so I don't think that would be an issue. Maybe I need to test my RAM to see if some of that has gone bad?

Things seemed to be working fine after the reset, though. The GF and I played Portal 2 the night before with some seriously laggy load screens... looking back, I'm wondering if that was related.

Any ideas on what to check from here? CHKDSK and SFC both came back clean, so I'm thinking the drives are fine.

 

Thanks for the help guys! Greatly appreciated!