Failed to open descriptor file ../../../

Trying to build on iOS using the launcher via editor sometimes it works and whenever I make some changes it brings up this message - any idea how to fix?

in my case I tried deleting the iPA in the binaries folder and rebuilding then relaunching, this seemed to work but I still have no idea why it happens because there are no errors in the output log

I too am constantly getting this. Sometimes it launches ok but then will not run a second time after I have quit the application and relaunched. I too delete the build.