To fix, you go into the properties page of your wireless connection, go to "Wireless Networks" tab and then to Properties of the chosen wireless network you are trying to connect to.
Then go to "authentification" tab and untick the box saying "Enable IEEE802.1x to the availiable network" and that should solve your problem Graham UKRight, Graham's solution worked for me.
It says something about windows not finding a certificate.
The weird part is that I was using WPA TKIP with the passphrase and it was working fine.
Then when all was lost I thought as "asdfsadf" did.