Itunes backup requires password to decrypt but password was never set

I'm trying to create a local backup of my Iphone using Itunes. When I create backups in itunes they are by default password protected (this is a fresh install of itunes and my Apple ID has only ever had 2 passwords) Ive tried my Iphone PIN, my old apple ID password and my current apple ID password. So far everything just says the password was incorrect. I've heard that you can reset your iphone settings to disable this but I'd like to avoid having to reconfigure my phone is there a solution that does not involve resetting my device?