Computer boots to C: only

GWL

New Member
#1
While easy BCD shows Bootmgr with Windows 7 Professional on Drive D:, it becomes drive C: after restarting and therefore doesn't work very well. How do I keep it booting on D: and the other windows os on C: ? Before the August windows critical update the computer always booted to D:, no problem. After that on rebooting it always boots to C: The drive has 2 partitions on it D: and C:
 

Terry60

Knows where his towel is.
Staff member
#2
"..doesn't work very well." ??
If that has really happened, then you won't get any further than the welcome screen and the PC will be unusable until you do this
How to restore the system/boot drive letter in Windows

but heed the warning at the beginning.
Changing the disk letter will make the PC unusable except in the specific case where you are correcting a problem where it has been accidentally changed from the installation setting.
If you are just concerned that EasyBCD is calling it D from another system, don't worry about that.
EasyBCD just reflects what the system it's running on sees. (There are no letters in the BCD. EasyBCD is just translating UIDs for you)
Each system has its own map of letters, and they are not in any way related to each other except by coincidence, so if all your OSs are C to themselves, they obviously cannot all been seen as C to each other, since the letter can only be mapped to one location on each system.

(Thread moved to Windows Support)
 
Last edited:

GWL

New Member
#3
Thanks for the thoughts, Terry. Here is a little more detail. Original windows installed on partition C: boots fine on C: when chosen in boot manager. Is this the registry to edit?
Windows 7, which had always been booting as D: until a few weeks ago, now tries to boot on C: when chosen in the boot manager. But while I can login the desktop doesn't show "My Computer" and only has broken shortcuts on the desktop. Very little works I assume because everything was installed when it was on D:. Adding a second hard drive with clones of partitions C:and D: before this partition switching was a problem allowed me to boot windows 7 as D: and most everything works OK except that the original windows os on C: is now at E: and a clone of windows 7 now resides on C:. At least it shows that the windows 7 when booted into D: still works. I did a little Regediting but all I saw were DOS devices identified correctly, but nothing specific to the problem. I even loaded the unbolted registry into a dummy hive to edit. Looked ok.
.
 

Terry60

Knows where his towel is.
Staff member
#4
You need to boot the problem OS as far as it will get and then run regedit. (luckily, unlike XP, Vista/7 gets far enough for regedit to work)
Use it to change the wrong entry (in your case C) to D, then reboot.
 

mqudsi

Mostly Harmless
Staff member
#6
Terry is our resident expert on switched drive letters :smile: