[Barrow4491]

Here is the result
Arduino: 1.8.3 (Windows 10), Board: "Arduino Nano, ATmega328"

Hi Jim,

When posting code on the forum, please use the "code" tag, otherwise its almost impossible read it.

The issue you are facing doesn't seem a problem with the AQM code, as it compiles fine.
It can be a problem with the USB cable, or be related to a possible bug in the Arduino IDE, where under some circumstances the code upload fails.

May there is a workaround...
Please post your AQM config file

Werk,
I swapped out the Nano and it compiled and uploaded OK. I powered the unit up but nothing seems to happen but I an unsure of what is supposed to.
Could you give me a brief outline of the procedure I should expect.
my config file is attached
Regards
Jim

// --------------------------------------------------------------------------------------
//   WeatherDuino - Air Quality Monitor v6.00 b004
//                  User Configurable Options 
// --------------------------------------------------------------------------------------

// --------------------------------------------------------------------------------------
//   Define ID and TX unit number
// --------------------------------------------------------------------------------------
#define StationID  0xA1      // Must be equal to your RX Unit (Value from 0x00 to 0xFF)  


// --------------------------------------------------------------------------------------
//   Define PMS7003 data set
// --------------------------------------------------------------------------------------
#define PMS7003_dataSet 1    // 0= CF1, 1= Ambiente (You should always use this data set)
#define use_RHcomp      1    // 1= Use RH compensation, 0= disabled

// --------------------------------------------------------------------------------------
//   Define if CO2 sensor is installed 
// --------------------------------------------------------------------------------------
#define Use_CO2 1            // 0= Not instaled, 1= Instaled


// --------------------------------------------------------------------------------------
//   Define type of Temperature / Humidity sensor
// --------------------------------------------------------------------------------------
#define TH_Sensor 1          // 1= HTU21D, 2= SHT2x, 3=SHT3x  


// --------------------------------------------------------------------------------------
//   Enable / Disable RF data transmission
// --------------------------------------------------------------------------------------
#define TX_Mode  1           // 0= No data will be transmitted via RF, 1= Transmit Data


// --------------------------------------------------------------------------------------
//   Enable / Disable Display 
// --------------------------------------------------------------------------------------
#define LCD_Display 1        // 0= Disable Display, 1= Enable Display


// --------------------------------------------------------------------------------------
//   Enable / Disable PMS7003 sensor Debug on Serial Monitor
// --------------------------------------------------------------------------------------
#define Debug_PMS7003 0      // 0= Disable 1= Enable


// --------------------------------------------------------------------------------------
//   Enable / Disable CO2 sensor Debug on Serial Monitor
// --------------------------------------------------------------------------------------
#define Debug_CO2     0      // 0= Disable 1= Enable


// --------------------------------------------------------------------------------------
//   SHT31 I2C Address - Default address will work most of the times!
// --------------------------------------------------------------------------------------
#define SHT31_address 0x44       // Default value is 0x44, but it can be changed to 0x45