HUB ERROR The project you are opening contains a locked library/Source assetDB file

A project closed accidentally while importing assets now getting an error:

The project you are opening contains a locked library/Source assetDB file and prevents you from re-opening the Editor or your project

How can i fix this?

I cant open any saved project i have it starts to load but then this error pops up asking me if i want to quit or retry?

Go to your project files → go to Library → and delete both artifactdb.lock and sourceassetdb lock.

That stuff took 4 hours of my work time.

Copying the project to another folder helped me…

Solved by deleting Library and Temp folder inside Unity project then restarting the computer.