Remote Assistance – “Problem with the invitation..”

Hi,

Does anyone know the soultion to the problem “There is a problem with the
invitation and it cannot be opened. To use Remote Assistance, the sender of
this invitation will have to send you a new invitation.”

MS have a kb 322182
http://support.microsoft.com/default.aspx?scid=kb%3Ben-us%3B322182

BUT I am offering remote assistance, not using OWA,any email client or
messenger. I am using XP SP2 in a 2003 SP1 AD.

Any ideas?