Got an iPad2 for work, set it up with an iTunes account I'd just created (my first one); downloaded apps, etc. Then got instructed to link the device to a work-created iTunes account, which was used for installing a bunch of standard apps for work (Numbers, Pages, etc).

Whenever I've gone to the App Store to download something, it asks for the password for one or other account - I don't know what determines which, but have just typed in the appropriate password. Ditto updates - it asks for one or the other, and I go ahead. Haven't bothered keeping track of which apps are under which account, but this hasn't been a problem.

Now I need to do a complete backup and sync (for updating the iOS), and I keep getting failure message, eg "Some of the purchased items on the iPad XXX including YYY could not be transferred to your iTunes library because you are not authorised for them on this computer." There's a whole list of apps that failed. Is this because of the two iTunes accounts? Is there a way around this, ensuring I have a complete backup/sync/transfer so that once I've updated to iOS 5 (currently on 4.3.5) I won't lose any apps?

Thanks!

<bump>, just in case anyone knows the answers...

You need to authorise that computer to use the other account as well.

Go into iTunes on the computer. If you're signed in to the work account (top right), click your name and select Sign Out.

Then click SIgn In, sign in with your personal account and you should get a pop-up asking you to authorise that computer with that account. If you don't, go to the menus at the top of iTunes and select Store then Authorise this computer. Hopefully that should fix it.