It appears that the problem began the the process of NIPM attempting to uninstall the 2019 version of ni-ssp-notifier. This has probably left your existing LabVIEW software installation in an "unfortunate state" with an old version (2019) "partially removed", but possibly with bits and pieces neither "completely installed" nor "completely uninstalled".
The safest (and possibly only) way to return your system to a stable "known" state is to completely remove, then reinstall, LabVIEW. First, make a list of what version(s) and Packages you want on your system (this is a great time to remove old versions you are not going to use any more. Then run NIPM, ask it to remove all installed packages (be sure you include everything -- be sure you have the "Projects Only" button unchecked. After you get rid of all the installed Packages, run NIPM once more and have it remove itself.
Now that NIPM is uninstalled, you can start re-installing those LabVIEW Versions and Packages that you want. When LabVIEW was originally released, the order that you installed LabVIEW was "oldest version first", with the newer versions sometimes over-writing or replaced older ones. This worked until shortly after NIPM was released. I spent about a year trying to get three or four versions (I don't quite remember, I think 2015, 2016, and 2017), and couldn't do it! I did about a dozen Install/Reinstall attempts, and had many (!) discussions with NI Tech Support. One very helpful technician (Marina) took my situation to the Developers, who told her to have me install the newest first, then install earlier versions. I didn't believe this, tried once more (failure), then "I Did It Her Way", and it worked!
Since then, NIPM has gotten a little better, but if Oldest First doesn't work, try Newest First.
Bob Schor
