On my 32-bit Windows XP machine I accidentially imported a .reg file that contained the whole HKCR branch of a 64-bit Windows 2003, now I have my HKCR with lots of redundant and maybe even erroneous data.
The machine is still alive, but I don't know how long it lasts. I guess there's a backup somewhere done by Windows. How do I restore it?
I've found this guide, but it requires a start-up disk which is not very fortunate. Are there any other ways?