accidentally removed msdebugger

A FEW WEEKS AGO, A FRIEND OF MY TEENAGE DAUGHTER SENT AN
EMAIL WARNING THAT A NEW VIRUS WAS BEING CIRCULATED
CALLED MSDEBUGGER AND EXPLAINED TO SEARCH FOR IT, WHICH I
DID AND DELETE IT. I DID THIS ON ALL THREE OF MY
COMPUTERS. THEN, SHE RECIEVED A LETTER FROM HER FRIEND
STATING THAT THIS WAS INCORRECT. HOW DO I AND WHERE DO I
FIND AND REINSTALL THE DEBUGGER WITHOUT TOTALLY
REFORMATTING AND REINSTALLING WINDOWS XP HOME EDITION?
NOW THERE ARE CERTAIN TIMES I SURF THE WEB AND IT SAYS I
MUST DEBUG, AND WHEN I TRY, IT CAN'T FIND A DEBUGGING
PROGRAM. PLEASE EMAIL DIRECT TO MY EMAIL ADDRESS.
THANK YOU SO MUCH.