Need Help - deleted user issue

So I have a user with a MacBook and a corresponding account on our server (using the iCal server). For reasons I won't go in to, I needed to delete the user and start from scratch. I deleted her account on SLS. It's gone. I then went to iCal prefs on the MacBook and deleted the server account in the Account pref in iCal. However, whenever I launch iCal again, it re-creating that server account and tries to connect to SLS, generating an error because the account is no longer there.

There must be a setting or leftover file or something on the MacBook causing it to recreate the account every time, but I just can't find it. Anyone have an idea? Is there something on SLS I need to do to "push out" the deletion and wipe something on the MacBook?