Something is blocking Process Monitor from collecting important info. I guess it is the same reason the MTA installer is failing.
Possible reasons:
1. Installed security software automatically restricting or sandboxing programs
2. A virus. Install something like https://www.malwarebytes.com/ and do a full scan
3. Corruption of systems files. https://support.microsoft.com/en-gb/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system