A common iPhone problem seems to be when syncing, many users get that nasty message, “Sync failed. Unknown error occurred (13019.)” The iPhone error 13019 seems to be most common if you have just downloaded the latest version of iTunes and oddly enough, if you have just upgraded your phone to 3.0. Weird that an upgrade causes errors, but that is all too true in many cases. And while Apple isn’t clear on exactly what causes this glitch, they do go on and on for pages and pages about how to fix it. Who knows why, really. It’s actually quite simple.
Start with your iPhone plugged in to your computer. If it starts syncing, just hit the “x” beside the sync status to stop it. Then find where it asks you in iTunes what you want to sync with your iPod and uncheck the box that says “Music.” Then allow the sync to start again, this time completing it. Be warned that this will erase all of the music off of your iPhone. But, once you’ve synced it, you can just place the music back in your iTunes library and sync it up again. Not only will you get your music back onto your iPhone, but you also won’t be seeing Error 13019 again!