Mountain Lion WiFi Problems (recap)

I have the same issue on my new MBA. I read on a post here that one guy unchecked the ituneshelper in the Login Items, so I tried that cause who needs it anyway and I have been been stable so far. Its worth a try. Good luck.

I really wish Apple would come out and admit that they have a problem and to fix it users need to do a clean install, I guess I'm going try this since my wifi problem persists, ugh. Thanks

Wow, the steps from that link have really helped! Thanks

Same here. Macbook Air 13", purchased a fewm months ago, stopped connecting to the internet after update to Mountain Lion. Will try a few tips given here before taking it to back the store.

Tell you what worked for me .. finally.

Had two Apple technicians on the case - over the phone. Have to say, those guys are awesome! - with patience of saints! But to the point! As there was nothing obviously wrong with operating system, they promised to call me back the following day but suggested talking to my Internet Service Provider about the router (D-Link router). The ISP remoted to my iMac and logged into router site and changed channel selection from automatic to manual. He chose channel 13, and suddenly my MBA connected and has been connecting smoothly ever since. The reasons I had problems was that there was over 10 available wi-fi networks in my flat, some of which showed as having stronger signal than my own. The ISP guy told me this, increasingly, becomes and issue, especially in blocks of flats - the ether is filled with wi-fi networks to the point of saturation. He also said, his choice of channel 13 was just a fluke and it might turn out I'd have to change it again.

So, although the problem is now solved, there still remains this one nagging question: Why did the wi-fi connectivity zonked right after Mountain Lion upgrade?

My problem was corrected (for 2 days now) when I followed Brandon's OSX daily tips and changed the MTU setting to manual and 1453... will keep you posted. Thanks for the head's up, Brandon!

If NONE of the other fixes are working for you, try changing your router channel from 6 (or whatever it currently is) to 11. After DAYS of working on this issue for hours on end, it is miraculous to me that the fix was a simple 5-second switch.

AGAIN, change your router channel to 11!