Remote Assistance "Profile" Issue

When attempting to connect to a user requesting Remote Assistance via
Windows Messenger, I get an error stating that the system could not load my
user profile. The connection appears to start, my remote assistance screen
loads, and what appears to be the "novice's" desktop appears in the remote
assistance screen (though totally black, due to this error).

There appears to be some sort of authentication that is failing here. I've
seen a similair prompt before with "roaming" user profiles.

The user is running WinXP Home. I'm not sure how I would verify on an XP
Home system 1.) What the user account that I'm impersonating for this remote
assistance is, and 2.) How to ensure that this account is not disabled. Has
anyone had any issues with this? Any advice would help...