Is there an error?
If so, what does it say?
Also, since Messenger Plus! is not the cause of the problem, try reporting it to microsoft:
http://support.msn.com/contactus_emailsupport.asp...enger&ct=eformfree
By the way, make sure if you report it to MS, not to say that you are using Messenger Plus!, because, they will tell that Plus! is causing the problem...