Tech folks - Windows Files and Settings Transfer

I don't recall having this problem before.

I back up the files to an external drive, wipe and reload Windows on the computer drive, then restore the F&S.

However - when I save the files now, the process also includes all my files on my external drive! WTHeck???

It did it correctly once - does anyone know the file extension or name of the saved files? I don't want to wipe out this drive and everything on it!

The reason I am using it on this computer is I don't trust myself to back up everything properly if I do it manually.

HELP.

Thanks!