I have the same problem.  I was installing the latest update PTXA2024.0.1  I installed it successfully on the server and 2 out of my 4 workstations.  On the third workstation it said there was a file missing and said it would uninstall the update.  I clicked okay and tried to run the update again.  Now, it states that the update needs to be done on the server first, but it already has been.  So, I tried to run the update on my fourth workstation and I get the same result.  

There must be a file on the server that states it has been updated and then the workstations look at that file before running the update?

Go to the data folder, look for a file named ~PVSW~.LOC, right click on it and choose properties, check the Read Only box and choose Apply.  See if that fixes the issue.