Alarm activating without reason

My 2002 Passat has suddenly developed a problem with the alarm going off within seconds of Remote-locking.

I reset the code according to the Manual (Or think I did)...No effect!
I made sure nothing was obstructing the doors hood or trunk...Waste of time!
I hung around for a half hour arming it and disarming it to see if it helps...It did not!
I locked one door and locked all just out of desperation...The despair is still painted on my face!
Only way it will not arm is if I leave the driver side unlocked by key...
Were I to do it by the "Key-remote" it still triggers the alarm and my frustration within 10 seconds.

I even read every entry in the Manual for advice...No Joy, may as well be in German!

Anyone have a solution for this irritating and quite uncomfortably dangerous problem?

Thank you.