changing boot drive letter???

From: jon (samuelsonj@carnegiemuseums.org)
Date: 12/31/02 

From: "jon" <samuelsonj@carnegiemuseums.org>
Date: Tue, 31 Dec 2002 08:17:43 -0800

can someone help me???.... i can't log in... because i
changed the drive letter.. although i've read the
knowledge base and still can't get threw it... can't i use
the fdisk /mbr???... help