Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: Remove system partition of old install

23 Nov 2010   #1

Windows 7 Ultimate x86
Remove system partition of old install

Hi everyone,

I have 2 hard drives in my computer, a 160GB and a 500GB. I wanted to transfer my windows install from the 160GB to the new 500GB drive, but I wanted to start fresh anyways, so I backed up all my important stuff, and did a clean install on to the 500GB hard drive, and set that as the primary boot device in my BIOS.

Now what I would like to do is format the other drive with the old install, so I can use it for backup/storage. The problem is Disk Management won't let me delete it because it is listed as "System, Active, Primary Partition". I figured this was because it is active, so I tried deleting it by booting from a GParted live cd, and deleted the partition. This was bad, as it seemed to mess up my MBR (perhaps for obvious reasons?).

So basically, I would like to know the best and safest method for doing this, preferably without any paid software.


My System SpecsSystem Spec

23 Nov 2010   #2
Microsoft MVP


Please post back a screenshot of your full Disk management drive map and listings, using Snipping Tool in Start Menu - attach file using Paper Clip in Reply Box.

If you kept the old OS HD plugged during the new Install, chances are the System Active boot files for the new install were written there. We'll need to look this over and give you the steps to correctly remove the old OS.

Be sure to tell us what is located where, and maximize the Disk mgmt output so we can see everything.,
My System SpecsSystem Spec
23 Nov 2010   #3

Windows 7 Ultimate x86

Thanks for the fast reply!

Here's the capture. The new OS installation is on disk1. The one to get rid of is on disk0. disk2 is just storage, not related to this problem.

Hope this helps!

Attached Thumbnails
Remove system partition of old install-capture.png  
My System SpecsSystem Spec

23 Nov 2010   #4
Microsoft MVP


As suspected because you kept the old OS HD plugged in during install, the new install put its boot files (System Active) on the old partition.

To correct this, mark the new Windows 7 partition Active, then mark the old Windows 7 partition Inactive using Diskpart from this tutorial: Partition - Mark as Active

Power Down to Disconnect the old Windows 7 HD to make sure it doesn't interfere, swap its cable to new Windows 7 HD or set it as first HD to boot in BIOS setup (after DVD drive). Boot the Windows 7 DVD Repair console or Repair CD, accept any offered Repair, when it doesn't restart boot back into DVD Repair, click through to Recovery Tools list to run Startup Repair up to 3 separate times with reboots to write the System MBR to Windows 7: Startup Repair - Run 3 Separate Times

After the new Windows 7 starts up, again power down to plug back in the old Windows 7 HD to clean it using Diskpart then repartition in Disk Mgmt: Disk - Clean and Clean All with Diskpart Command

If you'd prefer to have a graphical interface rather than using Diskpart to mark Active/Inactive, wipe the old HD and repartition, use free Partition Wizard bootable CD: Free Download Magic Partition Manager Software - Partition Wizard Online
My System SpecsSystem Spec
23 Nov 2010   #5

Windows 7 Ultimate x86


This solution worked great, other than some minor self-induced errors (like unplugging the wrong drive )

Thanks for your help!
My System SpecsSystem Spec

 Remove system partition of old install

Thread Tools

Similar help and support threads for2: Remove system partition of old install
Thread Forum
Can't remove old windows 7 install on other partition. Installation & Setup
Solved How to Remove Win8 bootloader for system MBR Partition Installation & Setup
Dual Boot - Can not remove one of the OS's, system partition Installation & Setup
Solved Remove partition after clean install? Installation & Setup
Solved Need to Resize or Remove System Reserved Partition Installation & Setup
Solved Remove System Reserved Partition+Partition Wizard Backup and Restore
remove system reserve partition Installation & Setup

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 01:18 AM.
Twitter Facebook Google+

Windows 7 Forums

Seven Forums Android App Seven Forums IOS App

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33