"Error: It looks like another Unity instance is running with this project open"

Sometimes when my project chashes and I try to open it again show this message. Usually I restart the OS to solve this. My quesiont is: How can I tell unity that there is not project left? killing a process? modifying a file?
I am a bit worried about trying to end a process and killing the unity ubuntu user interface.

 

When Unity closes unexpectedly it fails to delete a temporary file that prevents another instance of unity to open the same project. This file is located at [ProjectRootFolder]/Temp/UnityLockFile. So, you need to delete that file in order to open the project again without restarting the OS.

 

Same issue here... but the UnityLock file still exist because not all process are closed right.

Code (CSharp):

1. ps ax | grep Unity

 

ah thanks for explanation and for the command line help!

 

Also on a side to a the above, if you have your debugger attached to the process you get this. I need to close down mono or vsc

 

Awesome thanks! Deleting UnityLock fixed my issue. Side note, I first had to go into task manager > details, and force close Unity.exe before I could delete UnityLock.

 

We cannot do either on some of our computers, and when we do e still get the same error message.

 

@kentg1 - is the project on a shared network drive?? If so you may need to find the other machine that is accessing the project. .

 

Looks like Unity has fixed this problem - I got a email form tech support a few days ago saying that they would address it