The bane of my existence as a sysadmin was .NET. It would corrupt itself randomly, sometimes taking with it this awful CA product written in .NET that nobody else wanted anything to do with.
In my day I’d reinstall service packs and the latest patches and one of the six things we tried would fix it. I rarely knew which one. But that was five years ago. Today, as long as you’re running .NET 4.5.1 or earlier, Microsoft has an automated tool that repairs it. You can run it as a GUI app or from a command line or script. Curiously, it doesn’t support 4.5.2 yet–maybe that means 4.5.2 doesn’t break. We can dream, right?
Normally I’d say upgrade to 4.5.2 since its end of life is in 2023, as opposed to 2016, but until the fix gets revised to support 4.5.2, I won’t blame you for staying back on 4.5.1. Availability is 1/3 of security, after all.