I am not the only one reporting this issue. Moments after I updated I tried to use Airplay and the mirroring feature is unable to be checked. All I get is a blank screen on the TV. Extended desktop is the only option available which is a dark screen. I am not using an Apple Wireless router. I am using Netgear. iTunes Airplay works just fine. So I think it may be a SSL problem with the Netgear router. I don't know if Apple uses SSL in Airplay. Fortunately I have AirParrot which fills in for desktop computer streaming and works just fine. (8 bucks online download).
Unfortunately, you didn't specify what kind of equipment you have.
I am running a 2011 iMac i7 with 8 GB of RAM. Pretty clean system. No mucky networking tricks employed.
I have a solution for all you suffering from this problem to try. There is an Airparrot file, at least I think it is an Airparrot file as it is referred on the Airparrot site, that is called:
and it resides at: System/Library/Extensions
I have just moved this file to trash rebooted and I have got back Mirroring in Airplay.
I had previously installed Airparrot on a system I migrated to my 27 inch late 2013 iMac running Mavericks 10.9.2 and although I thought I had deleted it Airparrot fully prior to the migratio clearly I had not.
Having same issue after latest update. Apple TV appears in menu. On first connect as extended desktop, the apple TV would display the desktop. Dragging a video playing in safari onto the TV, the audio came through the TV but there was no safari to be seen. The apple TV then disconnected. My Macbook Pro (latest iteration) then refuses to connect to apple tv with message 'could not connect to apple tv'. The apple tv needs to reboot before the mac will connect to it again, then the problem is repeated with it not working properly.
I am not using airparrot. There appears to be a seperate issue with that.
I found that the mouse pointer will go across to the TV. Dragging any window onto the 2nd display causes it to break. The window never appears on the TV & the mouse pointer also disappears. The disconnection happens soon afterwards.
Problem Solved. I took the advice of other posters on other threads and totally uninstalled AirParrot. Airparrot has an uninstaller but you have to enter 2 additional commands if you are using 10.9.+. I originally thought AirParrot could coexist with Airplay. I GUESS NOT. After the uninstall and a reboot. Airplay ran perfectly. This is not Apples problem, it was because of a 3rd party application. PROBLEM SOLVED for me.
Problem Not Solved
The Air Parrot removal tool and steps listed here did not fix the airplay mirroring problem.
Removed Air Parrot, confirmed all files are gone.
I cannot connect to my 2nd or 3rd generation Apple TV with the iMac.
I can connect with my ipad & iPhone
In case any tech support happens upon this thread.
iMac 27-inch, Late 2012
Model Name: iMac
Model Identifier: iMac13,2
Processor Name: Intel Core i7
Processor Speed: 3.4 GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 8 MB
Memory: 32 GB
Boot ROM Version: IM131.010A.B05
SMC Version (system): 2.11f14
System Version: OS X 10.9.2 (13C64)
Kernel Version: Darwin 13.1.0
Boot Volume: Macintosh HD
Boot Mode: Normal