My macbook pro will not automatically reconnect to the wifi after a sleep. This has started after having upgraded to mountain Lion (10.8).

Hi

After I have installed Mountain Lion (10.8) - my macbook pro will not connect automatically to my preferred wifi network. It used to do that on the previous versions. It seems that the mac does not recognize the preferred network, as it asks me to choose a network after evey sleep/restart. I have modified the network preference to have my preferred netwrok at the top of the list. I have tried with/without checking the "ask me before joining a new network". It still behaved the same.

Thanks

Eitan