not sure but she could try resetting the router (back to factory condition) its not the same as unplugging and plugging in again. it reccommends a reset ONLY if you are having problems....i think we can agree on that one LoL.
to get to the router settings setup page, fire up a browser and type in the address bar
192.168.2.1 (this is for my Belkin router), i think its a universal thing but if needed refer to the manual. (please take care in the settings pages)
somwhere in there it will say restart router, or restore factory defaults.
maybe its a firewall conflict thats shutting down VPN, has she setup a home or small office network through windows or is she connecting through something like Real VNC?
and finally, does the problem still exist when using the desktop or is it just the laptop thats got the problem?
best i can offer at the mo, but for the benefit of others, can you tell us what windows, what VPN, any other info you think might be useful