VPN connection dialog box

I have a VPN connection configured on several computers that are permanently
LAN-connected for Internet access, but I only use the VPN ocassionally. With
varying frequency on the different computers, the VPN connection dialog box
pops-up while I do unrelated things. On ne computer, it happens in streaks
as often as once a minute or so. It is getting really annoying. I have
tried deleting the VPN connection and recreating it, checking each parameter
to make sure that nothing apparently indicates it is supposed to be always
connected or otherwise perfrom this way.

Any help on getting the VPN connection dialog box to come up only when I
intentiaonlly do so ?

Thanks.