This may sound strange but here it is:
Location 1: Laptop connects thru a dsl router using nat to office network
via vpn without any problems. Logs in perfectly.

Location 2: Same laptop, no router, direct to cable modem, no encrypted
packets received, actually one encrypted packet received, cannot login.

Location 3: Same laptop, router using nat to office, via vpn. Logs in

Does anybody have any ideas as to what could be the issue with location 2?