ColRay:
Arduino: 1.8.5 (Windows Store 1.8.10.0) (Windows 10), Board: "Arduino/Genuino Uno"c:\program files\windowsapps\arduinollc.arduinoide_1.8.10.0_x86__mdqgnx93n4wtt\hardware\tools\avr\bin../lib/gcc/avr/4.9.2/../../../../avr/bin/ar.exe: unable to rename 'core\core.a'; reason: File exists
exit status 1
Error compiling for board Arduino/Genuino Uno.This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.
Maybe you can try saving your project to a different filename .... just for test purpose.... and try compiling again.