Question regarding MikTeX update problems (or install problems) appear here from time to time. Like clockwork.
I suggest the following general-purpose solution: Use MikTeX "portable" version, rather than the installer.
The portable version is installed to your user home directory, where you do not need administrative privileges. That avoids one group of installer problems.
Once you get it working, make a zip archive of the entire installation for safe-keeping. Then, if some future update causes a problem, you can discard the installation, and revert to the un-zipped, known-good installation.
If the previously known-good installation fails (without update), then that suggests Windows has altered something in the operating system. If so, that's a problem; you will have to wait until MikTeX catches up. But I do not know of any occasion where this has happened.
There is still the possibility that an anti-virus program may object to some files.