By mistake I reinstalled Windows 7 Pro over the same Windows 7 Pro I had installed.
A windows.old folder was created, which looks to have all my previous data, users, programs etc.
How do I restore the 'old' folder to the same Windows 7 set up - Users/my documents/installed programs, etc.
The Windows 7 installation disc I have is an OEM disc.
Should I back up the windows.old folder as well
Just copy each folder (Documents, Music, Pictures, Videos etc.) to the "new" W7-folders.
Later, when you have confirmed that all your "old" files are where they should be, you delete the windows.old-folder.
But, i have another suggestion: create a new partition for all your files (Documents, Music, Pictures Videos etc). instead.
Create a partition.
Change the locations of the files (which is really simple).