Clear list of Windoze Messenger sign ins?

How does one clear the list of sign in names to Windows Messenger? One time, I typed my e-mail address, hit caps lock instead of tab, typed my PW, and hit enter…So there are two entries on the sign in list:

me@mye-mail.com
me@mye-mail.comMYPASSWORD

How do I clear that list?!