Situation: You have a problem to run Lightroom with this error:
“The Lightroom catalog cannot be opened because another application already has it opened.“
Troubleshooting: delete *.lrcat.lock.
When Lightroom is running, it creates a *.lrcat.lock file next to the *.lrcat file. if Lightroom is not shut down properly, the *.lrcat.lock file remains in the same folder as the .lrcat file, which prevents Lightroom from opening. In this case, you may delete or rename *.lrcat.lock.
By default, Lightroom *.lrcat.lock is located in the following folders:
- Windows: \Users\[user name]\Pictures\Lightroom
- Mac OS: /Users/[user name]/Pictures/Lightroom
Note: Close Lightroom when you delete the
*.lrcat.lock.
