not window striker, Door striker. Open your door and look at the b-pillar where your door's locking mechanism 'strikes' the b-pillar and latches. See the link below. http://cgi.ebay.com/ebaymotors/ws/eB...tem=8046922577
Some times the round part wears out and the little switch in the striker doesn't get depressed properly.
You can also do a search on this site for 'door striker'
Here's the link to a thread I had started when my striker was causing problems. There is a link within that thread that shows you a picture of the striker. http://www.bimmerwerkz.com/forum/3-s...t=door+striker
hope this helps. AND remember this may not be your problem, it was mine and it did effect my alarm eventually.