OK I have made some progress. First I. updated my Mac Software ti the latest MacOS Sequola 15.6.1. Next I permitted access to Discourse to allow it to access my computer for updates, Finally I ran the NoInterrupts code again and got this error message when I tried to compile it.
Users/mikecook/Documents/Arduino/libraries/Encoder/Encoder.h:76:7: warning: type 'struct Encoder' violates the C++ One Definition Rule [-Wodr]
class Encoder
^
/Users/mikecook/Documents/Arduino/libraries/Encoder/Encoder.h:76:7: note: a different type is defined in another translation unit
class Encoder
^
/Users/mikecook/Documents/Arduino/libraries/Encoder/Encoder.h:157:10: note: the first difference of corresponding definitions is field 'interrupts_in_use'
uint8_t interrupts_in_use;
^
/Users/mikecook/Library/Arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-objcopy -O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 /var/folders/0r/5d65776n19q2wvp1wf4bjsxr0000gn/T/arduino_build_486633/NoInterrupts.ino.elf /var/folders/0r/5d65776n19q2wvp1wf4bjsxr0000gn/T/arduino_build_486633/NoInterrupts.ino.eep
/Users/mikecook/Documents/Arduino/libraries/Encoder/Encoder.h:76:7: note: a type with different number of fields is defined in another translation unit
class Encoder
^
Any other comments other than I told you his code was not very good and portable?