Windows 7 Update Fail, Error 80073712

Computer Type: PC/Desktop
System Manufacturer/Model Number: me!
OS: Windows 10 Pro x64
CPU: AMD Ryzen 5 1600 @ 3.9GHz@1.3v
Motherboard: ASUS B350 PRIME-PLUS
Memory: G.Skill Flare X 16GB (2x8GB) DDR4-2400 @ 2666MHz
Graphics Card: Sapphire Radeon Vega 56 NITRO+
Sound Card: None
Monitor(s) Displays: ASUS VG248QZ
Screen Resolution: 1920x1080
Keyboard: Ducky Shine 6 w/ MX Browns and PBT keycaps
Mouse: Xtrfy M1-Ice
PSU: Corsair VS550
Case: Corsair Crystal 460X
Cooling: AMD Wraith Spire
Hard Drives: Samsung 850 EVO 250GB*, 1TB Seagate Constellation ES, 2x Samsung 840 250GB in RAID0* *Thanks ICIT2LOL for supplying me with all of these drives!
Internet Speed: 100MBit/s down, 20MBit/s up
Browser: Google Chrome
Antivirus: Bitdefender

Computer Type: Laptop
System Manufacturer/Model Number: Asus K52F or Lenovo B51-80
OS: Win 7 x64 Home Premium (and x86 VirtualBox VM)/Win10
CPU: i3 370M/i7 6500U
Motherboard: Asus/Lenovo
Memory: 8GB - finally :)/8GB
Graphics Card: it's an i3, dude!/dual Intel&nVidia
Sound Card: onboard
Monitor(s) Displays: 15.6" built-in
Screen Resolution: 1366x768/1920x1080
PSU: n/a
Hard Drives: 750GB Seagate internal Sundry external drives attached to other computers on the local network 1TB SSD on the Lenovo
Internet Speed: as much as I can get - usually on a dongle/phone, so <1MB/s
Browser: IE11/12/Edge/Chrome/FF(if I must)
Antivirus: MSE/Defender