sign in failure

hie again guys am having some problems accessing some services on my n95. its like i unlocked the handset from orange uk to use a 3 sim card again here in uk. everythind else is fine because 3 sent me there internet settings so am able to access there website and even connect to the internet using nokia search,opera mini,and even use voip applications like eqo and vyke mobile but i recently downloaded msn messenger via the download function on the applications folder but the msn messenger wont conect it says ;we were unable to conect windows live service,please check your access point and network settings and try again. i have done all this but still no luck i have even rang 3 network and they said these not much they can do about it since its not there handset what can i do please