Then, it's something within SP2 itself I assume (which winmsgr uses to connect to SIP).... Did you try to remove winmsgr 4.7.3000 first
(in the hope it also removes the "SIP-modules" (sorry, don't have a better name for it))? Because often, when you install an older product, newer DLL's and such aren't downgraded...
to remove winmsgr:
http://messenger.jonathankay.com/allsteps.aspx?ID=7
(note to others: do
not use this method to remove windows messenger if you aren't going to install another windows messenger version!!! This is not meant to "disable" windows messenger!!! instead read "
CookieRevised's reply to I am about to rip my hair out over MS Messanger" for that)
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