I wonder if you were seeing the same sort of thing that clobbered me.
If X1's installer fails to close all the programs running services, then it throws up its hands and gives up. In my case at least it had the grace to tell me that something had gone wrong.
By uninstalling X1, you eliminated that possibility.
If that happens again, you might find it easier simply to bring up Windows Task Manager, tell it to shut down all X1 services, and then retry the installation. That would be a bit quicker.
If X1's installer fails to close all the programs running services, then it throws up its hands and gives up. In my case at least it had the grace to tell me that something had gone wrong.
By uninstalling X1, you eliminated that possibility.
If that happens again, you might find it easier simply to bring up Windows Task Manager, tell it to shut down all X1 services, and then retry the installation. That would be a bit quicker.