the drivers in use are completely different between your old computer and the new one. You can plug it in and turn it on, but be prepared to spend a lot of time updating drivers, if it works at all. you should try booting into safe mode first, and then update your chipset drivers first. HP should have a list of drivers for your machine and the order to install them.
"This could only work if the two machines are reasonably similar (of same manufacture). However, be prepared that you'll need to re-activate Windows 7. If you'll wish to use the old Windows 7 serial number on the new machine, this might work, or you might need to explain (beg) the issue to Microsoft Support.
If the two machines are not similar, you'll need to reinstall all programs and copy all data. If you don't have written down all serial numbers and need to recuperate them, you can put the disk in the new machine and do a Safe reboot, recuperate the serials, then restore the new disk (the old disk can stay as a 2nd disk if there's place for it).
See this article : ""Top 13 Free Product Key Finder Programs""."
by the time you're done sorting out all the little tidbits (drivers, permissions, explaining to a microsoft rep why the activation has failed, etc.) you could have installed windows 7 from scratch on 10 machines.
