If a library sketch example appears in File > Examples > INCOMPATIBLE the currently selected board is not compatible with the library. For example, the Arduino UNO is incompatible with the ArduinoMotorCarrier library, and sketches from that library will appear in the INCOMPATIBLE category.
To use a sketch from this library, a supported board must be selected. To find out which boards are supported, search for the library in the Library Manager:
- Open (
Tools > Manage Libraries...). - Search for the library name, e.g.
ArduinoMotorCarrier. - Click More info.
For Arduino libraries, this will open the Arduino Library Reference.