SbiriJJ

If this happens the cause is probably you. If you want parallel installation you must use different directories, if directories overlap some will break. Get packages can broke an installation for various reason, any installation is different from others one thing is that some packages overlap because the packages is made in a wrong way. I have 4 installation version 7, 10.4, 11.3 and 12. All works with the only limit of some getit packages. More packages and other packages you add to your Delphi and more attention you must put when updates. Embarcadero cannot check in anyway if your configuration is compatible with another installation. My suggestion is to make a backup before new installation and also use backup when exporting or importing configurations and packages. You also can sandbox installations so all are isolated from others and can use same resources without altering them for other installations, but this practice is complex.