My old Mac Book Pro had serious problems trying to run Catilana.So I threw in the towel and bought this new one.The PC works very well.Catinlina has problems, like loosing files and is somewhat unstable.I have  hard drive which Catalina will not format with the new system.If I go bak to my old Mac I can reformat it and then it will work with Catalina.Jobs would never have let this sloppy programing out the door.Best suggestion is back up often.Because you may loose file any time.