Hi byte711,

Do I understand correctly that you have two 500-GB drives in a RAID 1 configuration?

Yes, that is correct.

I want to shrink/reduce drive C: to 150GB and create the remaining 350GB as drive D:.

The reason I want  to reduce drive C: to 150GB so when I perform a cold backup of drive C: the backup size would be a managable.

I can then store pictures, movies, whatever on Drive D: and have the protection of mirroring.

I understand I'll have mirroring protection on drive C:, but I want to perform cold backups on C: monthly, in case I need to back out a change that cause the system to become unstable.  Thanks!

Ok, but keep in mind there are limitations to the "shrink volume" utility. A few things you should do first:

1. Run the disk cleanup wizard.

2. Disable the pagefile (then delete pagefile.sys on reboot).

3. Disable system restore.

4. Disable the kernel debugger.

Another idea would be to do this manually. Break the RAID setup, re-partition C, then copy the system drive contents to the new partition. A third idea would be to use a third party program such as Partition Magic.

I did try the cleanup, defrag, disabled page file/delete, but never thought to disabling sys restore and the kernel debugger. That's interesting.

I even tried a 'Partition Magic' like app. I saw a lot of these apps had a Free Home Edition. They didn't seem to work, so I thought it was some kind of Win 7 mirroring restriction.

I ended up doing the 250/150 split. Which again is to much for me to leave to the OS & apps. I rather have the extra fault tolerance space for data type files. 150GB is plenty enough for me for the OS and whatever programs I install.

I guess I'll try rejoining the two partitions back together again and do the extra steps of disabling the sys rstr & kernel debugger. I don't feel comfortable at this time in breaking the RAID.

I'm curious, what would disabling the system restore and kernel debugger required to do this?

Thank you.

Both of those utilities can create immovable system files. If you can't move them, you can't shrink beyond the area on the drive where those files reside.

The System restore was disabled by default, I disabled kernel debugging, performed a defrag, and rebooted. Unfortunately, I still was not able to shrink drive C: below 250GB.

Do I need to turn kernel debugging back on or is this done after a reboo or even neccessaryt?

I would turn it back on. Should you have OS problems, it comes in handy.

Can anyone recommend a 3rd party app 'that they have used' that will do this?

Just received answer concerning this.

It's currently impossible in Window 7 64-bit with mirror drive to reduce the active partition half it's capacity. Not internally or 3rd party program.