How to abort a failed install?

I swapped a fairly new 500GB drive (that I had previously formatted to backup files) with the old XP system drive and installed Win7 Home Premium. However it is stuck at "Expanding Windows files (24%)" for three hours with not much activity on the HDD LED. Google seems to say this happens with the RCversion and just to wait, but it doesn't appear common for my Home Premium version.

I had also re-routed some cables (everything seemed OK in the BIOS) so should I keep waiting and see if I get a Win7 error code, or should I abort and try to re-install XP on the new-ish HDD to see if everything is OK with the PC, or if it was the Win7 disk? If so, how do I abort the install so I can try with XP?
Many thanks for any replies.

Forgot to add, should I have disconnected the old XP system HDD before trying to install Win7? The new 500GB drive was set as the boot drive and selected for the install, but I don't know if leaving the old XP system HDD in (to use for backups) would cause a problem.

stephens said:

I had also re-routed some cables (everything seemed OK in the BIOS) so should I keep waiting and see if I get a Win7 error code, or should I abort and try to re-install XP on the new-ish HDD to see if everything is OK with the PC, or if it was the Win7 disk? If so, how do I abort the install so I can try with XP?
Many thanks for any replies.

Stephens, welcome to the forums
There are indeed cases with the RC when it took a long time to install, but you probably have to start over. The best at this point is to turn the computer off, format that drive and start over.
Do disconnect the XP drive. Even if it is not messing with the install, you will probalby have a messed boot file after it is done; if you won't use XP anymore, just format that one too after you have 7 up and running. If you want double boot, pls check this thread

OK. Let us know if you succeed, or if you need additional support