Installing iOS 5 was going well until it came time to restore the backup. Enter the password to unlock your backup. Aaaarrrggghh! I tried the usual “clear” passwords that I use, every time I got an incorrect notice. In desperation I turned to 1Passport, although I was pretty sure I hadn’t told it about the iTunes backup security. It turns out I had, and it was a reasonably secure 1Password-generated string. Just goes to show…..
I panicked at first because if you don't know the password there is no way of restoring the data. It's a good idea to sit down, have a cup of coffee and think back. The password is not set to on by default so you must have done it purposely. It will almost certainly be one of your regularly used passwords. I was too clever for my own good and chose a randomly generated code. Fortunately, when doing this I would invariably store it in 1Password. I hope you can sort it out.
I have the same problem… no idea what to type in the password field…