@edith1966 - I had the same problem when I updated my 4S to iOS 6 and after many hours of troubleshooting I found a resolution; the steps below will detail this:
1. Connect your iDevice to your PC/Mac via the USB Cable and open iTunes
2. Scroll to the bottom of the summary page of your iDevice and remove the TICK from ' Sync over WiFi ' Box
3. Click Apply and close iTunes and restart your PC / Mac ( NOTE: Leave your iDevice plugged in )
4. Once restarted, open iTunes again, click on your iDevice under devices in the left hand pane of your iTunes window and select ' Summary ' at the top of iTunes
5. Scroll to the bottom of the summary page and place a tick in the ' Sync over WiFi ' box, click apply again
6. Close iTunes, and restart your PC/Mac
7. Also restart your iDevice ( no data or settings etc are lost ) by holding down both the Lock Button and Home Button until the White Apple appears on screen
8. Once restarted, open iTunes and then on your iDevice goto Settings - General - iTunes WiFi Sync
9. If the Sync Now button is highlighed you can unplug the cable from your phone and hit Sync Now
These are the steps that I found worked for me. I hope they help you also.
Thanks, that fixed my problem, where either looking for,or attempting to sync, the iPhone knocked out the Wifi connection to my Time Capsule (Airport Base Station), making iTunes unusable.
I followed your steps, but also needed to reboot the Time Capsule, and it worked!
Interestingly, my iPad can now 'not be found' at all, so I guess I have to do the same with that one!
The iTunes on my MacBook Pro 17 (Mountain Lion) would not sync with my iPad 3 and iPhone GS, both with IOS 6. Worked fine prior to the OS & IOS upgreade.
Today, I took my MBP, iPhone 3GS, and iPad 3 to the Apple store to try syncing at that location. I was unable to sync in the Apple store. I spent 30 minutes with technical support at the Genius Bar, but he was unable to make the syncing work properly. It will only sync using a USB cable. It will not sync in wireless mode. The strange part is that wireless syncing will occur occasionally. The mobile devices will mount properly in the iTunes Devices menu approximately 1 out of every 15-20 attempts.
The Genius Bar technician finally consulted with other technicians "in the back" and was informed that the problem I was having was an IOS 6/Mountain Lion "emerging issue" that would be addressed in a future update.
I checked the Apple support site to discover that hundreds of other Apple customers are having the same problem.
Had the same problem. Thru trial and error (Apple no help), here is what works for me. First try this: (1) uninstall itunes (2) restart computer (3) reinstall itunes. If itunes still doesn't see the iphone, thry this variation: (1) same steps as before, except this time, before reinstalling itunes, turn off the iphone (2) then, after reinstalling itunes, turn iphone on. I've had to do this several times since upgrading to IO6, so there must be a glitch somewher.
I solved the problem thru trial and error. The easiest solution is to turn off the iPhone before starting iTunes; then, turn on the phone after starting iTunes, and wait a few seconds. If that doesn't work, try uninstalling iTunes, turning off the phone, reinstalling iTunes, then turning on the phone. Both have worked for me.
Here is a good troubleshooting article from Apple on WiFi syncing at http://support.apple.com/kb/TS4062?viewlocale=en_US&locale=en_US
I noticed that when the Sync Now button on my device, iPhone or iPad, is grey it is because they are not on the same WiFi network as the Mac or PC. I had to change my devices to be on the same WiFi network as my Mac to resolve the problem (I have two WiFi networks in my home).
Not to be too obvious but it should be noted that WiFi sync does not work on 3G or 4G cell networks. WiFi must be enabled on each device and on the same WiFi network.
Hope this helps someone.
Great instructions and they worked for me BUT...
Imagine having to go through that EVERY TIME YOU WANT TO WIFI SYNC your iPad...
It's quicker to get a cable and plug it in.
It worked yesterday but it didn't work a few hours later and it ain't working now. Don't fancy spending 10 minutes or so restarting this and that and checking this box and unchecking that. Give me a cable any time.
Come on Apple, you've had long enough to look into this and fix and you still haven't got it sorted!
Isn't surprising that when someone has a problem such as this, people suggest different solutions that work for them, some of them time-consuming, some of them time-consuming as well as not working all the time, some of them that have to be repeated each time you have the problem because it doesn't address the cause?
There is a problem and NO AMOUNT of fiddling will solve it.
The problem is inherent in iTunes - in the software and if a solution works once, by fluke, it ain't gonna work again, and again, and again.
So we have to live with these silly little problems to nice features that Apple trumpets (such as WiFi sync) that DON'T WORK for everyone.