Hi dungx,  The error message "Unable to write to SetPara\System.ini" usually happen when the user ID which log in the Windows OS has no permission to modify the directory / drive where software installed.. I suggest you to try to enable & log in using "Administrator", not other ID(Even the other ID has admin permission).  Then lower down the UAC to the lowest level, and better to setup the security for the drive to be "full control" for "everyone"..