ITunes fails updating iPhone and iPad - works using another computer

Question

I am unable to update or restore the software on my iPhone 4 and my iPad 2. It always fails, sometimes with a 1013 error, sometimes with other errors.
It failed while attempting to update my iPhone to 4.3 and also while trying to update to 4.3.1.
I was also unable to update my iPad 2 to 4.3.1.
I connected the devices to another mac and was able to successfully update both devices the first time.
This problem occurred when running iTunes 10.2 and still occurs with 10.2.1.
I have also downloaded a fresh copy of iTunes 10.2.1 and still have the problem.
Can anyone think of a solution other than formatting and reinstalling everything?
My configuration is as follows:
MacBook Pro i5 2.4ghz Mid 2010
OS X 10.6.7
8gb RAM
iTunes 10.2.1

Answer 1

After updating iTunes to 10.2.2 it wiped out my iPhone, iPad and iPad2 and it will not restore on another pc in the house.  I spent 6 hours restoring the iPhone but the iPad and iPad2 has taken 6 hours going thru every step in the support recommendations as well as 3  hours on the phone with 2 separate techs today.
I uninstalled and reinstalled, went thru with the tech and edited the registry as well as the msconfig.  Rebooted the PC's, reinstalled, uninstalled all of the anti virus software and did a limited start-up, all to no avail.
You cannot reinstall the last working version of iTunes because the library is synced with a later version - so I have 2 dead devices.
Other friends are experiencing the same problem and I know of 2 dozen others experiencing the same issues.
Apple needs to fix the latest update of iTunes!