Problem:
You've configured a VPN to your office using PPTP (for Microsoft VPN) and it connects ok but doesn't route the traffic properly. Meaning you can't access any remote computers unless you tick the "Send all traffic over VPN connection" box. This however is not what you want. You don't want your internet traffic going via the VPN but if you don't tick this particular option it simply doesn't work.
Here's why:
IPv6. That's right. All you have to do is disable IPv6 in both your Ethernet Connection and the VPN settings. To do so, just select the TCP/IP tag and set "Configure IPv6" to OFF.
Voila, just by magic, everything works.