Cannot find binary 'avr-ar' exit status 1

Arduino: 1.8.5 (Windows 8.1), Board: "Arduino/Genuino Uno"

C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avr-gcc-ar: Cannot find binary 'avr-ar'

exit status 1
Error compiling for board Arduino/Genuino Uno.

I have no idea on how to solve this error, it was working fine days ago and I tried to delete and redownload Arduino but it still makes no difference :confused:

Check logs in your antivirus - mysteriously vanishing files like that often point to an overzealous antivirus program freaking out over the large amount of unusual-for-home-users activity that the arduino compile process involves. Since one of the executables seems to be missing, check the logs + quarentine on your antivirus.