Why your network printer won't print when connected to the VPN
A common problem with VPN connections is that they make using local network resources difficult. The reason for this is that, when connected, the VPN reconfigures the computer's network connection, making all your network traffic pass through it. When you connect to a VPN, the VPN software establishes a dedicated connection known as a tunnel to the VPN server in the FoxyProxy network.
This re-routing of data to a remote network may make it very difficult to access local network resources such as printers and routers. Printers connected directly to the computer aren't affected by this but printers in the Local Area Network(LAN) may become un-usaable while connected to the VPN.There are a number of ways to deal with this problem, the easiest of which is to disable the VPN, print and then reconnect to the VPN.
The second option is to add the print server to the routing table.There's an excellent article on how to do that here .
The last Option is to uncheck the "use default gateway on remote network" box under the TCP/IP properties in the VPN (if using Microsoft's default VPN client).