Multiple instances error and corrupt workspace.

[markgebert002]

I have recently been getting an error stating that I have "Multiple instances of Fusion 360 running." when I do not.

Upon opening, Fusion 360 displays a large black square square in the center of the normally white workspace. When trying to update Fusion 360, I get the following error message: "The update cannot proceed because multiple Fusion instances are currently running. Please close all other instances and try again." 

I do not have multiple instances of Fusion 360 running and in the past when Fusion would automatically close older instances if they existed.

[dooyoul_chung]

Hi @markgebert002
Thanks for sharing your experience. Could you please try again after restarting your PC? There may be a hanging process left behind causing the issue. Let us know if the problem persists after the restart.

[markgebert002]

After the restart, Fusion was able to update but the black square is still in the middle of the workspace.   I'm guessing your going to now want me to uninstall and then reinstall the whole Fusion 360 software package?

[markgebert002]

So I went ahead an uninstalled and then re-installed Fusion 360 using a new installer I downloaded from this site.   I am still getting a weird corrupted workspace with a black square in the center.  Note this is happening on two separate PC's running Windows 11.  The program was running fine for months and got corrupted two Saturdays ago after Autodesk did some system work on the site.

[jhackney1972]

You did not mention your operating system.  If Windows, enter your Task Manager and under Background Processes, look for Fusion entries.  Even if the application is closed sometimes errors will leave a background process running.

[markgebert002 · Accepted solution]

"Note this is happening on two separate PC's running Windows 11. "

I solved the problem and it seems to have nothing to do with Windows 11.  When I toggled the layout grid off and then on again, the square black object disappeared from the workspace.  See attachment.