wifi sync not working windows 7 64bit

Hi!

I have stumbled accross this thread, because my Wifi sync was not working anymore.

Since I am using both, IPv4 and IPv6, at home, turning off IPv6 for me is not an option.

This is my story and my solution.

However, for testing purposes I had turned off IPv6 on my Win7-64 machine a few weeks ago.

As time went by I forgot that I had switched IPv6 off on this machine which also has iTunes (with Wifi sync) installed.

Now for me it was the opposite case - turning on IPv6 again for my iTunes Windows machine, made the Wifi sync work again.

Why?

My router (Fritzbox 7390 with SixXS tunnel) gives out IPv6 prefixes for all devices, so as well for all iDevices.

All iDevices have an IPv4 address and several IPv6 addresses (link-local, global, etc.).

The iTunes machine was only using IPv4 and not IPv6, but the iDevices advertised themselves on IPv6.

So iTunes and the iDevices could not connect.

That's it!

I agree that the wifi sync thing seems to be mystic thing for a lot of people and the solution recipes are also sometimes very strange.

If you get a descent network sniffer (http://www.wireshark.org/download.html), you can find out what's wrong and why they do not see each other.

BTW:

I also have those interface index error of the bonjour service in my event log.

(ERROR: handle_resolve_request bad interfaceIndex X) where x=[1:24] with some number missing.

This is not a problem. Bonjours tries to open all network interfaces. On Windows they are identified by the interface index. You can see the used indexes on the command line: just type "route print" and you the first few lines will print the interface list. The number in front is the interface index.

You will recognize that the interface index of your main network adapter is missing in the list of "Bonjour bad interface index" messages in the event log. That is because Bonjour was able to open it successfully.

And I would like to bring to attention another "issue" that people should be aware of:

If your iDevice is running on battery, the Wifi falls asleep after a while if your are not interacting with it.

The only way of keeping the Wifi awake while you are not interacting with it is to plug in the power connector.

You can easily test this by "pinging" your iDevice from the command line.

You will see that after continuously pinging for some time, the "ping" suddenly times out if the iDevice is on battery and you are using it anymore.

So always make sure that the Wifi is running in the background if you want to use Wifi sync!

That's why Apple suggests to use power plugged into the iDevice if you are in the Wifi sync screen on your iDevice.

setting up the snmp from add/remove worked for me. I did all the firewall allows also mentioned all over the place to. This was the first time I saw SNMP mentioned. That seems to make the most sense on this being unstable.

I finally had success - make sure to separately uninstall Bonjour in addition to iTunes, the reinstall iTunes. First successful wifi sync in a couple years.

I have a solution which I haven't seen anywhere (although it probably applies to a small fraction of people with wifi sync issues... but, for those people, nothing else will help). I was unable to reliably use wifi sync on my Windows 7 box for a couple of years. I consulted many threads on the issue and tried them all and they all failed to fix it. Wifi sync would maybe work once after a reboot, or after I restarted the Bonjour service, but it would only work once. I think I finally discovered the cause: I removed a desktop widget called "Network Monitor" from addgadget.com. I discovered this when I tried to completely uninstall Bonjour; the uninstall wouldn't continue until I terminated the network monitor widget. I've removed the widget from my desktop and, since then, I've been able to wifi sync my iPhone and iPad about 4 times, with no problems.