VPN-Client Cisco reboots my computer

Archived from groups: comp.dcom.vpn (More info?)

Hi,
I've installed the Cisco VPN-client to build up a secure connection
requested by my university server. (Internet connection itself is via
DSL.)
Connection is built up fine. But as soon as I open any program
requesting data from or sending data to the internet, my computer
reboots - immediately, spontaneously and without any warning, error
messange or other possibility to find the reason why.
All configuration work didn't solve.
I use Win XP home; programs running in background are ZoneAlarm,
Free-Antivir.

Can anybody help?

Thanks in advance,

Burkhard