I'm not sure if my problem is the same as the original issue here or the many similar ones. But I have fixed it so will relate:
Recently upgraded to mavericks. But not THAT recently.
Out of the blue my MacBook Pro kept dropping wifi connection, while using, not necessarily on sleep. Would take ages to find the connection. And then it just got worse and worse, and when I tried to connect, a dialogue box told me I could not connect and to run diagnostics. No use that. Then I was asked for my password for the wifi... and although correct password entered, it did not take. Over and over again. Going to network connections I had this new dialogue about Thunderbold Bridge, never seen it before so did some searches and it appeared other users were having problems with wifi with this. So I disabled it, no change. I followed some suggestions: trashed SystemConfiguration folder fixed permissions several times (and of course rebooted etc). On the phone with Apple we reset PRAM and SMC - (and for some reason when setting SMC my green light on the power cord does not change as it should.. but never mind I hope). We deleted location, added new location etc etc. Tried it in Safe Mode and it seemed to work, although wifi VERY slow, but not working in a test user mode. Then the Apple care person got me to some new grey blank screen (sorry don't remember what it was) with internet password and Network login - but it would not accept my password. So he said I'd changed my password, which I hadn't.(we had other macs on this network doing just fine). We tried my IPod, and although it was working fine, once we 'forgot' the network, ti too would not accept the correct password.
He couldn't do anything for me at that point so I rang my profider, Plus Net, who showed me how to reset the router to original password. He told me probably I needed to upgrade my software on iPod and Mac but both are as up to date as possible ( I have old iPod). As I was near the router with my mac, I noticed that the issue seemed to be working... whether it was the router reset or not I didn't know. The iPod too. Accepted password (same old one..) and did not drop wifi. Back in my office.... which is very close to the router, and there are no interferring objects inbetween... the same problem happened. Dropped connection. Wouldn't pick it up. But was fine if I was next to the router.
Rang Apple. Finally got put through to a high level specialist including his direct number and email address. He suggested trying the delete keychain idea. As I have so many I had to copy and save all these which took me an hour and a half, and he was due to ring the next day. After saving all my passwords etc, and now on long ethernet cable in my office, I scrolled through these pages here.
I read about this:
setup your non-Apple wireless router to only use 801.11g as it seems to be 801.11n that Mavericks struggles with. My router at home has both an "n" channel and a guest "g" channel. I don't get any drop outs when I connect via the guest channel, but do when trying to use the faster "n" channel.
I went to my router and could find NO WAY to change this. It seemed set at 802.11b/g/n. BUT. I remembered from years ago a fix on another situation/computer/router: change the CHANNEL from automatic to a fixed channel. I chose Channel 1.
Problem fixed.
But WHY, and why I had a brief problem with the Ipod too, I don't know. As there have been absolutely no changes in our apartment in terms of what could be interfering - unless the neighbours are doing something. I'm not techincal so maybe someone here has an explanation.
Well so far so good. After 8 hours and many grey hairs. Hope the fix stays, if it doesn't I'll be back...