My CPU on my old PC recently blew up. The HDD was undamaged, and so I bought a new PC. It was formatted with NTFS, and it had critical data on it, which I had encrypted with EFS (Encrypting File System). When I reinstalled Windows XP on the first partition of the old HDD (because the new machine was so much better, and PnP could not have handled it), I found I could no longer access the critical files. I have the encryption certificates, but do not know how to use them to regain access to my data. Can anybody help??!
Not sure what you already tried but the google search as above will help if you explore it LOL.
I'll try to give you an answer but as always its probably gonna take some time and effort for you.
First you say you have the certificate, is it a MS generated or third party one?(certification authority)
Did you move the keys and folder to the partition that XP is on if not do this.Take ownership of folder in the NTFS security tab of folder.
Close properties go to my computer expand C: drive (or main drive) locate folder right click folder >properties>advanced tab>clear tic in "encrypt contents to secure data"
that should be it, if you don't have the right keys you I believe you might be out of luck because windows XP does not DRA (data recovery agents as of WIN 2K) in which a seperate key will be used to decrypt all files by a trusted ADMIN.
Well as I said above you might have to research this one a bit.Hope this helps a bit I havent been down that road in awhile but here is a link that explains it alittle better.