MTP USB Device drivers won't install no matter what i do

Computer Type: PC/Desktop
System Manufacturer/Model Number: Multiple (mainly Dell plus some HP business models, all second-hand)
OS: Windows 10 Pro (+ Windows 10 Home VMs for testing)
CPU: One i7 (which I almost never use), the rest all i5 or i3.
Motherboard: Dell mostly
Memory: Usually 8GB, rarely more (pensioner)
Graphics Card: Always onboard except for Xeon server
Sound Card: Always onboard
Monitor(s) Displays: 1 x 21" plus 2 others
Screen Resolution: All remain at defaults
Keyboard: USB
Mouse: USB
PSU: Y
Case: Multiple OEM.
Cooling: Defaults only
Hard Drives: Lots... a collection of nearly 40TB, although the Seagate 2TB ones are now failing frequently after 7 years usage.
Internet Speed: Currently, whatever 'Virgin on the ridiculous' provides
Browser: FireFox, mostly
Antivirus: Defender, mostly