[Kart41]

It seems that you have multiple copies of the same libraries installed. If insure about which libraries to delete, delete all copies of LiquidCrystal_I2C.h and Adafruit_HTU21DF, and install again the libraries included on the software package.

Thanks, that got rid of the multiple libraries, but the WD sketch still will not compile. 
Same error as above. Both the TX and RX sketches work fine.

I also tried v2.0_b005  it gets the same error.

Here is the current error:

Code:

Arduino: 1.8.2 (Windows 10), Board: "Arduino Nano, ATmega328"

D:\Arduino\WeatherDuinoPro2\Software\WeatherDuino_Pro2_Newest\software\WD software\WeatherDuino_Pro2_WD_v2.0_b008\WeatherDuino_Pro2_WD_v2.0_b008.ino: In function 'void setup()':

WeatherDuino_Pro2_WD_v2.0_b008:177: error: 'setSyncProvider' was not declared in this scope

    setSyncProvider(syncProvider);   // Sync system time with RTC

                                ^

WeatherDuino_Pro2_WD_v2.0_b008:178: error: 'setSyncInterval' was not declared in this scope

    setSyncInterval(86400);          // Every 24 hours

                         ^

D:\Arduino\WeatherDuinoPro2\Software\WeatherDuino_Pro2_Newest\software\WD software\WeatherDuino_Pro2_WD_v2.0_b008\WeatherDuino_Pro2_WD_v2.0_b008.ino: In function 'void loop()':

WeatherDuino_Pro2_WD_v2.0_b008:256: error: 'minute' was not declared in this scope

  if (minute() != last_min1)

             ^

WeatherDuino_Pro2_WD_v2.0_b008:277: error: 'second' was not declared in this scope

    if ((BackLight_State == true) && (second() != last_second))    // Clock update interval - 1s

                                             ^

D:\Arduino\WeatherDuinoPro2\Software\WeatherDuino_Pro2_Newest\software\WD software\WeatherDuino_Pro2_WD_v2.0_b008\D_TFT1.ino: In function 'void DisplayClock_TFT()':

D_TFT1:405: error: 'minute' was not declared in this scope

  if (last_min != minute())

                         ^

D_TFT1:407: error: 'hour' was not declared in this scope

    sprintf(Clock_buf, "%02d:%02d", hour(), minute());    

                                         ^

D_TFT1:412: error: 'day' was not declared in this scope

      sprintf(Clock_buf, "%02d-%02d-%d", day(), month(), year());

                                             ^

D_TFT1:412: error: 'month' was not declared in this scope

      sprintf(Clock_buf, "%02d-%02d-%d", day(), month(), year());

                                                      ^

D_TFT1:412: error: 'year' was not declared in this scope

      sprintf(Clock_buf, "%02d-%02d-%d", day(), month(), year());

                                                              ^

D_TFT1:414: error: 'year' was not declared in this scope

      sprintf(Clock_buf, "%d/%02d/%02d", year(), month(), day());

                                              ^

D_TFT1:414: error: 'month' was not declared in this scope

      sprintf(Clock_buf, "%d/%02d/%02d", year(), month(), day());

                                                       ^

D_TFT1:414: error: 'day' was not declared in this scope

      sprintf(Clock_buf, "%d/%02d/%02d", year(), month(), day());

                                                              ^

D_TFT1:422: error: 'second' was not declared in this scope

  if (second()%2)

             ^

D:\Arduino\WeatherDuinoPro2\Software\WeatherDuino_Pro2_Newest\software\WD software\WeatherDuino_Pro2_WD_v2.0_b008\RX.ino: In function 'void ReceiveDataRF()':

RX:124: error: 'setTime' was not declared in this scope

    setTime(Hora, Minuto, 1, RX_Data[4], RX_Data[3], RX_Data[2] + 1900);

                                                                      ^

exit status 1
'setSyncProvider' was not declared in this scope

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