I've tried to update my macbook pro to osx 10.8.4. While my macbook rebooted, it said, that the update failed. After this failed update, my Mac will no longer connect to my TL-WR841N router.
I clicked the OK button and waited until it completely started. Then I tried to connect to my wlan (with no success). I got a "Connection timeout.". So I disabled/re-enabled my wlan, removed the wlan interface in the network panel, rebooted my macbook, added the network panel and got rid of the connection timeout. But it wasn't working: I got the error, that I couldn't connect to this network. I tried a lot: Repaired the access privileges in the utility program, changed my location in the network panel. I also reseted my router, but this was not the problem, because I could connect to it with my iphone without problems.
Then I discovered that I can connect to every network that has no encryption or has WEP encryption. I changed my wlan security settings in my router to "NO" and "WEP" (just for testing) and I could connect. But when I change it to WPA or WPA2 I can not connect (Yes, the password is right)..
What can I do now? How can I solve that? OSX 10.8.4 log says that it improves some points concerning wlan, so I think it has something to do with that. However beside the wlan my macbook is working great and (in contrast to the error message when updating), the "About Mac" panel says OSX 10.8.4.
Best Answer
Since the update told you it failed, you might need to re-apply the update by connecting to a wired network or downloading the whole update from another computer if yours is off the network.
Be sure to download the 10.8.4 Combo updater and re-apply the update to be sure the drivers all installed properly and no pieces of your software were missing or corrupted. Since normal updates are a delta (only the changed items get written), it's a slim chance that something odd happened and a re-install of the patch might help fix things up for you.
Once you've gotten the OS X update installed, should the problem persist, you can troubleshoot it as normal. The two avenues I would pursue to troubleshoot this would be to dig into Wireless Diagnostic first to see if it can identify your issue.
This tool is substantially better on 10.8.4 than it was on previous versions (when it was called Wi-Fi Diagnostics) and it has helped me solve several tricky network issues already.
The second would be to go into the Network preference pane and clear all known wireless network settings: