Tip: Archive iPhone backup in Windows
iTunes normally maintains one rolling backup for each device unless you restore a backup in which case it is archived with the date of the restore and a new rolling backup created. On a Mac you can get iTunes to duplicate a backup set, but that feature isn't replicated in iTunes for Windows. With iTunes closed you can select, then copy and paste an existing backup folder set in C:\Users\<User>\AppData\Roaming\Apple Computer\MobileSync\Backup and then give it a folder name that ends in -yyyymmdd-hhmmss. When you restart iTunes the extra backup set will be listed under Edit > Preferences > Devices although it will have the same same as the original it was cloned from. Once you refresh the active backup it should be possible to tell which is which from the time stamps.
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