How do you cancel an editor process?

I accidentally duplicated a folder containing a scene I wanted to duplicate, rather than just the scene itself. I can't find a way to kill the resulting length import process. Please can someone tell be how to do this.

I've tried killing Unity, mono processes and rebooting, but when I re open Unity it just starts the process again. My machine has sounded like a hairdrier struggling to process this for about 20 minutes now and the green bar is tiny. At this rate of progress I think I'll need to leave my PC on for a couple of days before I can do anything again.

This has happened before on other processes, such as accidental builds. There must be a way to stop this but searches haven't turned up anything. Please help.

 

Anyone? The glaciers are melting ever so slightly faster now.

 

If you just duplicated the folder you could remove the folder outside of unity in the explorer / finder and then reopen unity.

 

Thanks but this didn't work. Maybe the files are cached somewhere. The import continue...

Is it really the case there is no way to cancel a process in Unity once it has started? It seems ridiculous that one erroneous keyboard shortcut can lock you out of your project for hours, with no option to cancel

I'm glad I didn't duplicate the parent folder