Recurring BOOTMGR is Missing error


Feb 23, 2010
Andddd I'm back. Managed to break my PC again in my usual form...

So I recently bought a new SSD and did a fresh installation of Windows 7 on it. Everything boots fine - until I get nitpicky about the boot times and start changing some settings in the BIOS.

To give some background, I was initially trying to resolve a problem with slow boot times on my GIGABYTE P55A-UDL3. There is a 10sec delay after the "Loading Operating System" message. Windows splash screen onwards only takes 5 secs. I read somewhere that this had to do with having the CD-Rom as the first boot device. (Don't even want to get started on the AHCI BIOS itself already adding another 2-3secs)

Anyway, if I recall correctly I did some (supposedly harmless stuff like) moving my SSD to the #1 priority in the BIOS list and also set Hard Disk as the first (and only) Boot Device.

Boom. BOOTMGR is Missing.

That's pretty easy to tackle. I pop my Win7 CD in, run the Startup Repair etc etc. Boot into Windows, no issue. Fixed!

Then I restart my computer again. Same error again!

Fix. And again.


I tried a combination of things like putting back CD-Rom as my first Boot Device, but I think I have broken something else.

In addition, the Startup utility is identifying my Windows Installation as E: drive, which is correct.... only in CMD. In Windows / Explorer itself, my SSD with the Windows installation is on the C: drive. I only have a singular Windows installation.

Currently in Disk Management,

Disk 0:
D: 100MB of the annoying System Reserved partition. Marked Active. This I believe is leftover from some ancient installation.
E: Simply a data partition. To store multimedia files, backups, no programs.

Disk 1:
C: My SSD and Windows installation. (Boot, Active, Crash Dump, Primary Partition)

Disk 2:
G: A second data partition. I install all my programs here. It is labelled as System, Page File, Active, Primary Partition

That can't be right. I think it's the root of my problem.

All in all my issues listed in priority:
1) How do I stop BOOTMGR from recurring during reboot after fix?
2) How do I reassign the incorrect labels in Disk Management (System on G: moved to C:)
3) How do I remove the 100MB unused System Reserved partition without reformatting the HDD?
4) Am I able to remove CD-Rom drive from the BIOS boot order, opting to manually activate it when required? (Pressing F12)
5) Would Step #4 shorten my boot times?
6) How can I further shorten the boot times with AHCI BIOS on a Gigabyte motherboard?

Thanks for your patience!


Apr 8, 2011
It sounds like your boot partition is on one of the other drives Disconnect the 2 drives and leave only your drive with windows on it. then boot with your windows 7 disk and run startup and repair. This will put the boot record on the same disk as windows. sometimes disk management will not give the correct drive letters. Also set your bios to boot from the CD/DVD first. If you start moving drive letters you may have more problems then you want. when win 7 is working again then you can format the other drives if you want


Feb 23, 2010
Thanks almartin. Simple and elegant solution. Yes, turns out BOOTMGR must've been confused and fixed it for the wrong drive(s).

The anomalies I mentioned in Computer Management are also gone now!

I guess I should just Format the drive with that stupid 100MB partition if there's no other way. Just hope that doesn't cause anything (else) to break.


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