Some iOS 9 update users getting ‘Software Update Failed’ error message — here’s a workaround
It’s not just you.
Most iPhone and iPad users attempting to update to iOS 9 are seeing an error message on the first day the new operating system is available to the public.
After attempting the update on the device, users are seeing, “Software Update Failed: An error occurred while downloading iOS 9.”
Users seeing the error message said they were able to successfully update their operating system by plugging the device into a computer and using iTunes to perform the download and update.
This appears to be the only confirmed workaround at this time.
Apple has not commented on the error message, however it’s probably safe to assume demand for the new operating system overwhelmed Apple’s servers.