wifi lost after update

I have just updated my X10 with 2.3.3 and now can't get a wi fi connection. Previously it was great and always connected automatically to my home and work networks.Now,although the wi fi box is ticked it constantly says scanning and then disconnected. I've checked all the forums, turned it off and on, taken out the battery and tried Fix My Wifi. Can anyone help me? It would be appreciated, thanks.