Fixing Windows 10 Boot Problems

June 29, 2018 at 9:19 pm (computers) (, , , )

Had an issue with a Windows 10 laptop where it stopped booting.  It was failing at the flashing cursor on a black screen, which to me looked like either a disk failure or some odd boot loop.  It wasn’t registering that there wasn’t an OS and it wasn’t trying to boot an OS and finding errors.

Booting off a Windows repair CD didn’t get anywhere with startup repair either, so into the command line I had to go.

There are a number of Windows commands that relate to boot that came into play:

diskpart – to look at disks and partitions to work out how it is configured (using the commands “list disk”, “select disk 0”, “list partition”, “list volume”, etc)

bootsect – to fix the boot sector (in this case, I used “bootsect /nt60 sys”)

bootrec – to fix various boot and boot record issues – “bootrec /fixmbr”, “bootrec /fixboot”, and finally “bootrec /rebuildbcd”.

Unfortunately rebuildbcd (bcd = boot configuration data) generated an error, “the file or directory is corrupted and unreadable”.  So after a bit of Googling, then also found bcdboot.  This is supposed to setup the boot environment by copying the relevant files form the Windows installation over to the boot area.  Running that though, came up with more errors, so poking around in the two areas, the PC had a boot partition on C: and the system drive was D:.  It was attempting to copy from d:\windows\boot\pcat to c:\boot and failing for some reason.

So at this point, I thought a chkdsk might have been in order – so “chkdsk /f c:” came up with a load of index errors related to all the language files which it seemed to fix.  bcdboot was still struggling, so I manually copied the rest of the files over.

At this point bcdboot largely succeeded, but still had one error, so running it in verbose mode highlighted a problem accessing the bcd catalogue from the d:/windows/system32/config area.  But not really knowing what it was trying to do with it, in the end I just ran “bootrec /rebuildbcd” and that seemed to work fine this time.

At this point, we felt it worth attempting a boot again, and thankfully at this point.  It all worked.  Windows did its own chkdsk again whilst starting up and we were finally in once again.

Kevin

 

 

Advertisements

Permalink Leave a Comment