a challenge for gurus

[x]

Hi,

I have windows xp, and the newest version of messenger.

on the computer there are 3 users, user A,B an C. When I log in as
user A, I will get the automatic repair re-install messenger window to
popup and proceed with repairing IF user B or C have been logged in
before user A.

For users B and C, they log in and recieve the same repair and
re-install messenger window to popup and proceed with repairing IF
user A was previously logged in.

BUT if A was logged in previously, and then A is the next user to log
in, then it does not repair messenger.

if B or C was logged in previously, and B or C logs in it does not
repair messenger.

Any ideas?