I made a partition in active and now windows 7 (x64) wont boot

Hi guys,

I have two hard drives, one which was running my old OS and the other i was using as storage. I got a virus which affected the OS and forced me to install a different version of windows on the second drive (the one i was using for storage). I ended up installing Vista and then upgrading it to Windows 7 x64 Ultimate. This worked and i was able to use my computer fine.

I then decided to try and reformat my original drive to avoid the posibility of the virus jumping over somehow. I had some difficulty doing this as Windows wouldnt let me format the active drive, so after reading around a bit, i went into the DOS prompt to make it inactive. After restarting the computer, i now reach as far as the 'verifying DMI pool data' line before nothing else happens.

Ive now realised that the boot files may have been put onto the 'original' drive, even though i installed windows 7 of the second drive and now i cannot access them.
I have tried putting the disc in and running the repair DOS prompt and making the partition active again, but this hasnt worked.

Is there any other way i can get it to boot again?
Thanks in advance for any help

Yep, simple fix is to remove the hard drive without Windows on it from the machine, temporarily. Set the remaining drive to be the first boot drive in the bios and save.

Then boot to the Windows 7 DVD and run a Repair Install. One time should do it, but up to three consecutive runs may be necessary.

When it's all fixed, reinstall the drive you removed. Then check bios that the other drive is still the fist boot device.

hi, thanks for the quick reply!
I have unplugged the unwanted drive, and run a startup repair with the disc like you mentioned. The first time it restarted but didnt work again, so i ran it a second time. This time it came up with a window that said "startup repair cannot repair this computer automatically" and it listed the problems as "Problem event name: StartupRepairOffline .... Problem Signature 07: CorruptBootConfigData"
I also noticed when it searches for the installed OS at the start of the repair, it finds windows 7, but it says partition size is 0, and its on an (unknown)Local Disk..
Does any of this help?

Remove all external drives such as USB sticks or HDDs. Then try again with the process.

the only things plugged in at the moment are the mouse, keyboard and monitor and the same thing happens.

Just an update, Now when i turn the computer on, the monitor isnt working. The orange light stays on as if it isnt registering that the computer is on, which it is. The computer light is on, and i can hear it running.


Excellent Member
Microsoft Community Contributor
From your description, you installed Vista on the second drive, which meant the boot files were placed on the primary drive. Torrent G suggested you remove the primary drive and do a repair to the secondary drive.

You can only boot to an active partition. One thing the repair option does not seem to be good at is making a partition active. I would suggest you download a partition manager, such as Partition Wizard, and booting to it to make sure the partition containing the boot files, or OS, is active. Partition Wizard has changed their website, so look for a bootable, free version to use to burn and boot to so you can make the partition active. Once it is active, the repair options work much better. A Linux version, GParted, is also available.

thanks for the help guys, i think i might be in a little over my head so i decided to take it down and get a pro to have a look at it. Thanks again

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