Version 3.47 can sometimes encounter installer issues on Windows 10 or 11. To ensure a smooth installation: Run the installer in for Windows 7.
The compiler is a legacy tool used for Microchip's PIC18 microcontrollers. Finding a "full version" can be tricky because Microchip transitioned to the XC8 compiler years ago, which now supports all 8-bit PIC devices. mplab c18 347 full version best