Windows V7 Pro will not boor. OS now indicated as being drive d:

So what the issue sounds like is that bootmgr is missing, this has happened to me in disk management the active partition has been set to D: the way i fixed was a reinstall however check the link :

http://pcsupport.about.com/od/findbyerrormessage/a/bootmgr-is-missing.htm

Also, have you tried booting into safe mode to do this, if you can get there what you may have to do is go into safe mode with command prompt and try and set C: to active in the list of disks

can't get into safe mode either. I can get into a command prompt, but how do I set c: to active in the list if disks?

Please see this link : https://support.microsoft.com/kb/300415

Where was the OS installed on C: or D: which has the system files ?

the original installation was on drive c: when I boot into the repair mode, the files are all on drive d:. there is also a drive c: but this is labeled as "system reserved" and appears to be empty.

thanks

you are correct.

when I run diskpart I can see that volume 1 which us c is assigned to system rese and the original boot disk is assigned to d:.

ok - I have managed to switch the letter assignments using diskpart & assign, but when I re boot the drive letters have switched back again??

help!

many thanks

when I run bcdedit, the windows boot loader indicates the device with partition=d: and the osdevice with partition=d:

it seems that these have been changed somehow, but how do I fix it?

many thanks

i think this isn't possible the whole operating system would need to be reinstalled and when reinstalling it, format drive C: and then select it to install on

Hi.

Next time please provide a proper error description in the first place. The IDE/AHCI issue would have been solved in seconds :)

I gave all the information available. there was no specific error message. it just failed to boot.

Ok, if I set my sata controller from AHCI to IDE compatibility mode, then it won't boot but shows a bluescreen (a flashing one). If I chose to hit F8 and select not to restart automatically, I can even read the blue screen contents. For me (as for you) they would have displayed 0x000..7b which indicates the boot device is inaccessible - which would never be seen if the drive letters were mixed up (because at that early stage, letters are not even used).

This should only show you that indeed "all the information available" was nowhere to be seen here. :)

there was no blue screen just the option to start normally or enter repair mode. thanks for your help.

***hope you won't call me a smart ass - just meant helpful***
Well, you just did not see the blue screen as the default setting is to auto-restart. As I wrote: you would need to hit F8 to turn auto-restart off in order to see it.

I accept my own solution as I found the answer elsewhere.

many thanks to all