unlocking problem on my w211

and i have a little problem with it ! i explain : yesterday the car car was ok i put it in the garage and this morning the car w'ont open by the key so i taked the little metal key and opened manually by the driver door ! infortunately the alrm gone on ! and when i put the key it won't turn it stills in 0 position without the little noise ok debarring !! can someone help me ? did it happen to one of you ? i verified the fuse all was ok ! changed the key battery but unfortunatly nothing !
i cutted the battery ..... i checked all !
please can you help me or give some advices ?
thinks to you in advance !!
im happy to be in this forum


