In my other two PCs, the Top path (.....sam > ) does not exist.
From https://github.com/arduino/ArduinoCore-sam/issues/19:Almost certainly not. Try this:Tools > Board > Arduino/Genuino UnoFile > Examples > Wire > digital_potentiometerSketch > Show sketch folderTools > Board > Arduino DueFile > Examples > Wire > digital_potentiometerSketch > Show sketch folderYou will now see that you have two different Wire folders. One is in the libraries subfolder of your Arduino AVR Boards hardware package, the other in the libraries subfolder of your Arduino SAM Boards package. It's easy to think it's only one library because of the standardized API and the IDE automatically choosing the correct library based on board selection.
https://www.arduino.cc/en/Reference/WireNoteThere are both 7- and 8-bit versions of I2C addresses. 7 bits identify the device, and the eighth bit determines if it's being written to or read from. The Wire library uses 7 bit addresses throughout. If you have a datasheet or sample code that uses 8 bit address, you'll want to drop the low bit (i.e. shift the value one bit to the right), yielding an address between 0 and 127. However the addresses from 0 to 7 are not used because are reserved so the first address that can be used is 8. Please note that a pull-up resistor is needed when connecting SDA/SCL pins. Please refer to the examples for more informations. MEGA 2560 board has pull-up resistors on pins 20 - 21 onboard.