After upgrading to Catalina, I tried opening my Photos Library, on an external Seagate drive, but it appeared to get stuck updating at 54%. I started again a few times, but each time it appeared to start the count over again. After two days I closed and tried to reopen Photos but it would not reopen. Frustrated, I ran Clean My Mac and it opened right away. It had actually finished updating my Library of 120,000 images. Maybe when all of the updates add up to 100% you are all done, but Photos won't open. Maybe, also Clean My Mac found and fixed the problem?
[Total: 0 Average: 0]