Change iTunes backup location

iTunes consistently attempts to store device backups on C: regardless of where it is installed. I need to change this location in order to backup devices to my PC.

PC: HP 750-247c

Processor: Intel Core i7-6700 @ 3.40 GHz 64-Bit with 24.0 GB RAM

OS: Windows 10 Home v1607

OS Build: 14393.1358

iTunes Version: 12.6.1.25

Devices: iPhone SE and iPad Mini 2

iOS: Both running iOS 10.3.2

My computer has two hard disk drives, C: and D: C: is a solid state drive that is only 120GB and is used only for operating system files and critical programs. My D: is a regular HDD with 2.0 TB of capacity.

I purposefully installed iTunes to D: and have (manually) moved my iTunes library to D:, but I cannot get iTunes to natively recognize D: as a storage location. Upon installation, iTunes creates its standard folders hierarchy and installs files in the C:\Users\<user>\AppData\ directory regardless. It also defaults to saving device backups to the following directory: "C:\Users\<user>\AppData\Roaming\Apple Computer\MobileSync\Backup"

There is no option to change this directory. Therefore, even though I know in advance that there is not enough storage available on C: (and over 1 TB available on D:), I cannot tell iTunes to use the location with the available space.

The most popular "helpful" support article I've found so far using Google search has been the following post, from 2013: https://discussions.apple.com/thread/4977359?answerId=27069714022#27069714022
Unfortunately, these command prompts do not work in a Windows 10 environment.

If such a setting is possible, how can I change iTunes so that it will install ALL files and folders, and save backups to, the directory location of choice?

If such a setting is NOT possible, PLEASE ADD IT ASAP!

Looking forward to replies and assistance. Thank you in advance!

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