I have been getting this issue for many recent versions of unity. Basically, I keep updating with the hope that It would be fixed in a certain version. But it still happens. I have seen other forum threads from a long time ago address a similar issue, but I don't know if the causes are the same. And I did try the solutions that were mentioned in that thread, which seemed to work, but after restarting my computer, it continues to do the same thing again. Basically, when I launch my project through Unity Hub, as you normally should, I will get stuck on the loading window as shown in this image. And the "busy time" will keep going up forever. I can fix this by then going into the Task Manager is force quitting Unity and relaunching, and it launches 100%. But then if I shut down and start up my computer, I have to do the same thing all over again... Annoyingly... I'm not 100% sure if deleting the library folder actually fixes the issue. I tried it, but I still get this issue the next day (after PC shutdown). I don't know if maybe it's associated with a file of sorts??? And the file causes unity to take infinite time to import because it keeps "retrying"? No clue. I forget which exact version of Unity I had this issue in, but I know most of the versions I've had this issue with are all 2021.1 Right now I am in 2021.1.19f1 But I have updated versions at least 5 times, but those versions were still 2021.1.XXf1 etc etc.