Run those commands in a the comand line
takeown /F "G:\Program Files" /A /R /D Y
icacls "G:\Program Files" /T /grant administrators:F
rd /s /q "G:\Program Files"
takeown /F "G:\Program Files (x86)" /A /R /D Y
icacls "G:\Program Files (x86)" /T /grant administrators:F
rd /s /q "G:\Program Files (x86)"
takeown /F "G:\Windows" /A /R /D Y
icacls "G:\Windows" /T /grant administrators:F
rd /s /q "G:\Windows"