Nothing's worse than when you're pretty sure you need to use Windows System Restore function to do a rollback to get your XP system up and running again, but it just refuses to boot into either normal or safe modes. The most common causes for such a situation are Malware or a software update which somehow went wrong and corrupted the system.
If this is the case you currently find yourself in, hopefully the following may be of help and work for you.
This can also be carried out by booting from a live Linux or WinPE disc, but it also works with the drive attached to another Windows system which is the method described.
You need to remove the hard drive from the affected system and attach it to another system either directly or using an USB hard drive caddy.
On the system you have the drive attached to you will need to make system and hidden files visible;
In Control Panel select Folder options and then the View tab. In the Advanced setting you need to ensure that "Show hidden files, folders and drives" is selected. You also need to remove the tick from "Hide protected operating system files"; expect to get a warning message from windows and click to accept the change.
Once you've done this, the fun starts.
It is imperative that the following changes are only applied to the hard drive which you're trying to fix and not to the drive of the system you have the drive attached to.
Access the drive through My Computer or Window's explorer. There should be a folder on it called "System Volume Information". When you open it you need to navigate to:
You should then hopefully have a buch of folders beginning with "RP"; select and open an RP folder created on a date prior to when the problem started. To find out when it was created you can right click on it, select properties and this will show the creation date.
Open the RP folder you selected and then open the folder called Snapshot. Copy the following two files;
[drive letter]:\WINDOWS\system32\config - and paste the files you copied into it.
You then need to re-name another two files in that folder, (without file endings), called "software" and "system" to something like "softwarex" and "systemx".
Once that's been done you need to re-name the two files you previously copied in to it to; "software" and "system" respectively.
Shut down the system and replace the drive into the original system, it should boot to Windows XP normally.
There is no guarantee of success, as this may not be the solution for your particular problem. It may also be necessary to repeat the process choosing RP folders created earlier than the one originally chosen,