My C00D07C9 problem is SOLVED! Read below.
I have a Samsung Focus and a Samsung Focus S. For no reason at all, my Focus S stopped syncing wirelessly. I tried removing wireless sync from Zune and re-configuring it, but then I started getting error C00D07C9. I tried absolutely EVERYTHING in this thread
including rebooting my phone and my computer, removing and re-adding the wireless network on my phone, completely uninstalling and re-installing the Zune software (including manually scouring the registry and deleting every single file and folder with the
word Zune in it) - I turned my firewall on my computer completely off, I ran ZuneDevices.exe to monitor for SSDP and UPNP messages, I set a DHCP reservation for the MAC address of my phone on my router, I changed the name of my phone to remove all the spaces,
I even installed a wireless network card into my computer and tried connecting the computer to the same wireless network as the phone. NOTHING WORKED (C00D07C9)!
Finally, with no hope of a solution, I tried upgrading the firmware on my router because some people said it solved their problem and voila. Miraculously and inexplicably my wireless sync is now working. I have a Cisco RV220W firewall/router and I upgraded
to a firmware version 1.3.x and now my phone wireless sync is working again.
This makes absolutely no sense and I can't explain what caused the sync to stop working in the first place, but I am just happy it is working again. Hope it helps somebody.