Installing iTunes 12.4.1.6 update on Windows 7, 64 bit

I currently have iTunes version 12.3.2.35 installed on my Windows 7 64 bit machine. I kept getting prompted to install an update, lately for version 12.4.1.6 but the installer keeps failing with a message about a mysterious missing program.

"There is a problem with this Windows Installer package. A program required for this install to complete could not be run. contact your support personnel or package vendor."

There is no indication as to what program is supposedly missing. My machine is up to date and has plenty of processor, memory and space available.

Any idea what the issue could be or how to resolve it?