Windows 7 - Can I move MBR to different hard drive?

Hi all i am running a dual boot setup i have XP on one HD and 7 on the other, it seems that the MBR is installed on the HD which has XP installed on it as i found out when i unplugged it 7 would not boot up!! I am looking to remove the HD with XP as I dont use it, can i move the MBR to the HD with 7 on?

hope you can help

Craney

Yes, first mark Windows 7 active in XP Disk Management, or using free Partition Wizard bootable CD.

Next unplug XP HD, boot into Windows 7 DVD Repair console or Repair CD, click through to Recovery Tools list to run Startup Repair up to 3 separate times with reboots to write the MBR to Windows 7.

Good question. You can change the active OS in XP by modifying boot.ini as explained here:
How to edit the Boot.ini file in Windows XP
However for 7, you can use bcdedit command line or try the easybcd tool that was made for vista, I don't know if it works on 7 or not if they have a new version:
Download EasyBCD 1.7.2 - NeoSmart Technologies

cool cheers for that, it does seem to be 7 that is the active OS as this is what it boots into if i do not choose, so would the best way to do it be unplug the hd with XP boot up the 7 dvd and reapir the MBR that way?

I do have the easy BCD installed on the xp hd but not to sure on how to use it

thanks again

You should do as Gregrocker suggests and mark the Win 7 partition or the Win 7 System Reserved partition (if you have one) active. Then disconnect the XP drive...

What happens? If it won't boot, run the startup repair, as suggested.