ICS issues with Roku

[Incredidave]

I'm trying to set up my Roku by connecting it to my desktop and using ICS (to let the Roku make use of the much better signal that the desktop gets).

This works fine, the Roku connects and can stream easily. Unfortunately, the desktop now seems to have something wrong with it's connection, things like Steam and Teamspeak are fine and stay working, but I can't load any webpages, ping or tracert from cmd.

I figure something might be wrong with the DNS, but resetting all the different components hasn't helped.

Does anyone have any ideas?

Thanks