Error 3259 with iOS 5 updating on iPad

When I try to download the iOS 5 update to my iPad 2, I get the error code 3259 while "processing files". My computer is runnning Windows 7 with Kaspasky. Try rebooting the devices, turning off antivirus and Firewall software, all to no avail.If you have the same iOS 5 download problem, try the following steps.* Download directly the update from your internet browser.* In iTunes, press and hold