Hi, this is my first post.

I have 70 ipads in the school where I am technician, I use Conigurator 1.5 (newest I think) and i have just updated all iPads to iOS 7.1. My problem is that most of the iPads updated fine, but as I'm doing them in groups of 10 one of the groups failed to update and they all went into recovery! I have restored them all individually in iTunes so they are now back to factory settings, fortunately i made backups of them all in configurator so I tried putting them back in to restore these backups. This is where the real problem starts! 5 of the 10 iPads restored fine, no problem, but the other 5 are not restoring, they come up with random error codes. Most common is error code 4 and it says: backup is encrypted. Which they are but all the others were fine, they ask for a password and once I have entered it they restore fine. These last 5 though are still not restoring to the backups i cannot work out what has happened, can anyone help? Thanks