I promise apple and everyone else, I did not forget my passcode. It has to be a glitch. My wife's phone uses this passcode, my phone uses it, my ipad uses it...I did not forget it.
I did this also.
think i found a solution but you must know your apple ID and PW.
1. sign into icloud.com
2. once you are signed in click on "find my iphone" tab
3. click "all devices" on top of the page
4. click on the device you lost your passcode to.
5. once you do a couple of choices will come up "play sound" "lost mode" and "erase iphone"
click on the erase iphone. and it will begin to whip out your iphone.
6. once i was done i connected it back into my itunes and restored from my last backup. i was then
able to get into my phone and reset my passcode. :-)
hope this helps. i was so lost i thought i messed up big time lol.
I am in the same boat. For some reason the passcode I have used since owning this phone and re-entered today when upgrading no longer will unlock the phone. I am stuck also. Same error message same issues.