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Windows 7: Computer won't boot due. Most likely wrong disk set to Active?

24 Jun 2012   #1

Windows 7 Ultimate 64bit
Computer won't boot due. Most likely wrong disk set to Active?

Hey umm well I was playing around with my newly built desktop and trying to sort out my hard drive and such I accidently set a disk to "active" thinking it would do nothing I went about my business and continued to use my desktop until the following day.

So just an 1 hour ago I tried to boot up my desktop and was greeted with
"BOOT MGR IS MISSING - Cltrl+alt+delete to reboot"

I more or less knew that the disk I was messing with last night had caused this. So I grabbed my windows disk and started up and went straight into command prompt to sort it out. However now I have set my windows disk to active and all others to inactive my computer is still telling me Boot Mgr is missing, and yes I have changed it so it will boot from my Hard Drive but still.......No luck

Any help would be greatly appreciated! Any more information needed just ask

Thanks Tom

My System SpecsSystem Spec
24 Jun 2012   #2

Windows 7 Ultimate 64bit

Don't worry about it....Problem Solved.
My System SpecsSystem Spec
24 Jun 2012   #3

Windows 10 Pro X64

Mind sharing what the fix was?
My System SpecsSystem Spec

24 Jun 2012   #4


Partitiions are set Active, not disks. If you set another partition Active than the WIn7 or it's System Reserved boot partition (preferred if you have it) then you need to move the Active flag back where it was: Mark Partition Active

If Win7 doesn't start then you'll also need to Startup Repair - Run 3 Separate Times.
My System SpecsSystem Spec
24 Jun 2012   #5

Windows 7 Ultimate 64bit

Thanks for the correction Gregrocker.

Umm the fix was to access command prompt on the installation disk and access DISKPART where I checked the volume names and remembered that part of my SSD was partitioned to "System Reserve" I soon realised it was this partition that need to be active and went about this ensuring all other partitions were inactive and the "System Reserve" was active.


The rest I followed the same steps as above but with each other partition I would change it to "Inactive" Then eventually exit "cmd" and reboot ensuring it was booting from my SSD.

(Disk0 and Partition 1 in my circumstance)
My System SpecsSystem Spec
24 Jun 2012   #6


Since only one partition on a HD can be marked Active at a time, it isn't necessary to mark the others Inactive.
My System SpecsSystem Spec
24 Jun 2012   #7

Windows 7 Ultimate 64bit

I suppose you are correct however I ensured that the other partitions weren't active by ensuring they were all inactive.

Not unless when you make one active the others automatically become inactive? If this is the case I didn't know that and will remember for future use. However if not then doing what I did caused no harm. =D
My System SpecsSystem Spec

 Computer won't boot due. Most likely wrong disk set to Active?

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