iTunes app sync fails - "pairing file."

New iPhone WiFi refuses to connect to network (despite many hours trying) so trying to download apps via iTunes.

First attempt received message about a problem with the "pairing files." Would have read the message more carefully if I knew it would never appear again.

iTunes backs up phones, flashes message suggesting that app sync has begun - then ends quickly -> no sync of apps.

Reboot PC and restarted iTunes but no change in problem.

Nothing but problems from new iPhone. Cool interface - but basic stuff does not work or way hard to set up. I thought the Apple world was supposed to be easier - not harder - than the "PC" world. Guess I am learning the hard way.