When I try and synchronise my iPhone with iTunes, I get a dialog informing me that "syncing has been disabled on this computer". (I've never disabled syncing myself, and it worked perfectly fine a day ago) Music synchronises fine, as do videos, however, my contacts do not. Google Contacts no longer appears in the list to choose from, and the select box is empty.

When I choose to re-enable syncing, iTunes informs me that "iTunes was unable to load provider data from Sync Services". I've followed several steps I've found on the internet, including deleting the C:\Users\Ryan\AppData\Roaming\Apple Computer\Sync Services directory, but to no avail.

Any ideas on what could be causing this? Is there a Service (in the Windows-form-of-daemon sense) that I accidentally disabled?