Possible Duplicate:
Restoring Windows XP PATH variable
Upon installing Ruby and Instiki, my PATH got replaced completely with c:\ruby\bin.
Obviously, it never occured to me that any installer would do something like that, so I've no backup, nor any idea what was in the old one (but there was quite a bit in there).
Is there any way of restoring an old PATH variable?
(ideas given in similar question to this one, produced no results)