OK - re-installed from scratch and created a blank new project with main.cpp as follows:
;
Build using the PlatformIO build:
> Executing task in folder Datalogger_Ethernet_New: C:\Users\StephenRogers\.platformio\penv\Scripts\pio.exe run --environment uno_wifi_rev2 <
Processing uno_wifi_rev2 (platform: atmelmegaavr; board: uno_wifi_rev2; framework: arduino)
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Verbose mode can be enabled via `-v, --verbose` option
CONFIGURATION: https://docs.platformio.org/page/boards/atmelmegaavr/uno_wifi_rev2.html
PLATFORM: Atmel megaAVR (1.3.0) > Arduino Uno WiFi Rev2
HARDWARE: ATMEGA4809 16MHz, 6KB RAM, 47.50KB Flash
PACKAGES:
- framework-arduino-megaavr 1.8.6
- toolchain-atmelavr 1.70300.191015 (7.3.0)
LDF: Library Dependency Finder -> http://bit.ly/configure-pio-ldf
LDF Modes: Finder ~ chain, Compatibility ~ soft
Found 5 compatible libraries
Scanning dependencies...
No dependencies
Building in release mode
Compiling .pio\build\uno_wifi_rev2\FrameworkArduinoVariant\variant.c.o
'avr-gcc' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\src\main.cpp.o
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\CDC.cpp.o
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\NANO_compat.cpp.o
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\Tone.cpp.o
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\UART.cpp.o
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\UART0.cpp.o
'avr-g++' is not recognized as an internal or external command,
Compiling .pio\build\uno_wifi_rev2\FrameworkArduino\UART1.cpp.o
operable program or batch file.
*** [.pio\build\uno_wifi_rev2\FrameworkArduinoVariant\variant.c.o] Error 1
*** [.pio\build\uno_wifi_rev2\src\main.cpp.o] Error 1
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\CDC.cpp.o] Error 1
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\NANO_compat.cpp.o] Error 1
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\Tone.cpp.o] Error 1
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\UART.cpp.o] Error 1
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\UART0.cpp.o] Error 1
'avr-g++' is not recognized as an internal or external command,
operable program or batch file.
*** [.pio\build\uno_wifi_rev2\FrameworkArduino\UART1.cpp.o] Error 1
============================================================================ [FAILED] Took 0.91 seconds ============================================================================
The terminal process "C:\Users\StephenRogers\.platformio\penv\Scripts\pio.exe 'run', '--environment', 'uno_wifi_rev2'" terminated with exit code: 1.
I have also checked that those conflicting VSCode Extensions are not there. C/C++ is required by PlatformIO it says but that is the only extension other than PlatformIO IDE itself that would seem to conflict.
I also reinitialized the project to rebuild intellisense.
These sure seem like unexpected errors. I have also watched some tutorials for PlatformIO and these types of results are not in them.