Chromecast not working

[#1]

Hello, I wondered if someone might be able to help me please...
My Chromecast has stopped working. It was running fine on Friday and today it wasn't working. I've reset it and have received an error to say I need to 'disable Access point/AP isolation'
I've logged onto my router: Thomson TG585 v8 but I can't see where/how to disable this. UPnP is enabled but I'm still getting the error.
Can anyone help and advise please?
Thanks

[#2]

I've not used the PlusNet router so I can't give you any exact instructions but I found this on Google which might help you:
Login to the router, go to the Wireless Settings page and make sure that Wireless isolation (under Wireless Access Point) is un-ticked.
If you have to un-tick it, make sure you click on the button labelled "Apply" on the page.
Have a look here for further instructions if above does not work.
http://helpforum.sky.com/t5/Unlimited-Lite-Connect-broadband/Chromecast-won-t-connect-through-router...

Its always a good idea to make a note of what settings you change just in case it does not correct the problem and you can easily change
them back to there defaults.