Ill try to make this short and sweet. For months I successfully ran a time machine backup daily with an external HD connected to my Airport extreme. I recently changed the security setting to WEP so that it would supports some of my older wireless devices. It then stopped backing up "the back up disk is unavailable" etc. From here I completely reformatted my external HD to OS Extended Journaled, and also configured my AE back to the way it was originally, security settings and all (basically started from scratch again). I have tried EVERYTHING and looked all over the web, but I still cannot get my wireless backups to work again. The time machine utility recognizes the disk, but when selected, it still tells me that the "disk is not available". What am I doing wrong? I have tried numerous codes in terminal that worked for others on the web but they did not work for me. With my luck it seems like it is something very minor, however I am doing nothing different than what I did the first time around. Thanks in advance, any help is greatly appreciated.