>>If you have any other network gear in common (that are shared by the 3 problem VPNs) such as switches, routers, cable or DSL modems, you could try rebooting those.
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>Thanks for the help
>
>However, if that would be the case, this means we wouldn't be able to access the VPN from other laptops in my network.

OK, I guess I didn't understand your initial post. It now sounds like:

- you have several machines at your location, on the same physical LAN
- there are 3 other networks you connect to via VPN (i.e. geographically separated from you, not on your own LAN), e.g. clients
- you can connect to these 3 other networks via VPN from some of your own computers (e.g. the laptops), but not others

If this is the case:

- what is common amongst the machines that cannot connect, vs. the ones that can?
- do the non-functional machines use firewall or AV software different from the functioning ones?
- even if functional machines share some things with non-functional ones (e.g. network switch) it still may be worth trying a reboot of the switch. Or, try plugging the cable from the non-functioning machine into the switch port of one that works. I've seen switches partially fail from being hit by power spikes/brownouts etc.