This has happened to me a number of times. I am notified of App Updates. So in iTunes I download the updates. I then try to Sync with my iPhone. I then get a message indicating that they could not update due to unknown error. I then remove the applications from my phone and re-sync. This then works. However, for most I lose my data and have to start over. Does anyone else have this problem and is there a solution? Also, I do have most of my applications on menu page 2 but the page 1 applications also have the same problem.