User accounts - looking for account

Under User accounts, only two accounts are listed:

Donald R. Culp (administrator) -- password xxxxxxxx (not the real password).
Guest -- no password.

When I boot the computer the logon name in the logon dialog box is Don Culp.
However, this logon name accepts the password from Donald R. Culp. (These
are both me.)

Where is the Don Culp logon name stored so that I can change it to Donald R.
Culp?

XP Pro, service pack 2.

Thanks.


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