I have a long running problem with Wi-Fi Sync and haven't been able to solve it.
My iPhone will not sync over Wi-Fi. On my iPhone, when I go to Settings app → General iTunes Wi-Fi Sync, the Sync Now option is greyed out, and I get a message saying Sync will resume when (computer name) is available.
I've checked that both the iPhone and the laptop are on the same network, logged in with same account in iTunes and enabled Wi-Fi Sync both in iTunes and on the iPhone.
To solve the problem I have a so far tried:
Updated to latest version of iOS and iTunes.
Turned off firewall and antivirus.
Tried to sync at different locations, different routers, different ISPs, etc.
Uninstalled iTunes, cleaned registry with CCleaner, reinstalled iTunes.
Cleared sync history.
I also found a few months ago that even when I upgraded to a newer iPhone and transferred all my files and user data to the new phone using iTunes back up, the new phone would not sync over Wi-Fi. Maybe there is a bug in some setting that is getting transferred across.
I'm out of ideas. Does anyone have any suggestions please? Preferably without totally wiping my iPhone and losing everything on it.