Parralells 5, can't activate windows because unable to connect to internet

I know that Paralells 5 is no longer supported, however I've just installed a recommended update for 5 - 200 Mb+ download so don't want to waste that if at all possible.

The Problem. When trying to activate Windows, Paralells won't connect to the internet, my internet connection is working - WiFi via wireless modem, and after many tries I've given up.
I've looked at the connections settings but everything seems in order.

I'm running Mac OS X 10.6.8 on an 24" intel iMac.

My fear is that if I upgrade to Parra 8 that I will have this problem again, so I'd like to solve it with Parra 5 first if possible.