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Windows 7: Dual Boot Question/Unable To Find System Disk

30 Jan 2012   #1

Windows 7
Dual Boot Question/Unable To Find System Disk

I currently have two separate hard drives in my home PC. My C: drive has Windows Vista on it and my X: drive has Windows 7 on it. The system is dual booted and if I choose either operating system, it boots fine to whichever OS I choose.

My issue is this: If I disconnect one of the drives (either one), I get an error after BIOS that it cannot find the system disk. I know which drive is C: vs. X: while looking inside my case.

My goal is to remove the drive with Vista on it to use in another PC (given drive prices are through the roof today). I just want to keep my drive with Windows 7 on it (currently labeled in the system as drive X).

Is there a way around this without having to format my drive (X) with Windows 7 on it AFTER I remove the C: drive with Vista on it?

Sorry if this all sounds confusing. Thanks in advance for the help.

My System SpecsSystem Spec
30 Jan 2012   #2

Windows 7 Ultimate SP1 64-Bit

Welcome to Windows Seven Forums.

A screenshot of your disk management layout would be a big help.

In the meantime I would have thought that carrying out a startup repair would sort out your boot problems.

Startup Repair - Run 3 Separate Times

In my humble opinion you probably have the boot files on the Vista drive so that when you disconnect it the computer is looking for your C drive - it can't find Windows 7 because you have it on the X drive.

When you've removed the Vista drive and got Windows 7 booting correctly, you need to change its drive letter to C.
My System SpecsSystem Spec
30 Jan 2012   #3

Windows 7

Thanks for the reply. Is it possible to change the drive letter without going into Windows or can I change it after booting in to Windows?
My System SpecsSystem Spec

30 Jan 2012   #4
Microsoft MVP


You cannot change an OS drive letter as it will ruin it in every case.

If Win7 is not C when booted it is because the installer was incorrectly run from Vista which blocked out the availability of the letter so that Win7 couldn't assume C whenever booted, as it does when it's installer is correctly booted.

If you need to remove Vista then we need to see the requested screenshot to advise you the exact steps as there are unknowns that need to be seen first. Use the Snipping Tool in Start menu, maximize Disk Mgmt, capture a rectangular snip of the drive map with listings, post back using Paper Clilp in reply box. Screen Shots
My System SpecsSystem Spec
30 Jan 2012   #5

Windows 7

Here you go:

Attached Thumbnails
Dual Boot Question/Unable To Find System Disk-capture.jpg  
My System SpecsSystem Spec
30 Jan 2012   #6
Microsoft MVP


You can Reinstall Windows 7 if it matters to you that it is not on C drive.

To remove Vista, mark Win7 partition Active: Partition - Mark as Active

Then power down, unplug Vista HD, swap its data cable to Win7 HD or enter BIOS setup to set Win7 HD first HD to boot, after DVD drive.

Next boot into Win7 DVD Repair console or System Repair Disk to run Startup Repair - Run 3 Separate Times until Win7 starts on its own.

You can then plug back in the old Vista HD, if you need to boot it use the one-time BIOS Boot Menu key. When ready to delete it use Diskpart Clean Command then repartition in Disk Management. Partition or Volume - Create New
My System SpecsSystem Spec
31 Jan 2012   #7

Microsoft Community Contributor Award Recipient


Help me get windows 7 to boot (again)

Quote   Quote: Originally Posted by theog View Post
Attachment 168313

Physically disconnect the two Vista HD above.

Make the Win dows 7 HD, disk0 & first HD boot in BIOS.

Attachment 168310

Do a Startup Repair:

Startup Repair

Note: You may need to do startup repair 3 to 4 times.

Startup Repair - Run 3 Separate Times

Attachment 168311

When Windows is booting OK, Reconnect the other two Vista HD, as Disk1 & Disk2.

Attachment 168312

Mark all other HD Drive INACTIVE.
Partition - Mark as Inactive
My System SpecsSystem Spec

 Dual Boot Question/Unable To Find System Disk

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