Arduino sketch wont upload

Hello Blynkers,

Last time i uploaded this sketch on my arduino mega:

  if (Serial.available())


int drukdata =;

if (drukdata=='a')

do something   

After I tested this sketch I wanted to use my arduino for blynk again.
But i couldn’t upload my blynk sketch to the arduino.
Compiling works fine and after i press upload i don’t see any errors appear.

This picture is what the arduino IDE looks like for hours after trying to upload.

Is it possible that i can’t upload my sketch due to the serial port which is busy by the arduino checking for communication?

Kind regards,


It seems you have invalid libraries. Try and remove all libraries except the ones you use from the user library folder indicated. Can you post the whole finished sketch? Because the way it is now it’s not gonna compile since you don’t have the “do something” as comment, but the principle should be fine.

( I think you are Dutch, or at least Dutch speaking, if you can’t get it to run you can send me a PM and I will try and explain in Dutch :slight_smile: )

Send me a PM anyway, this doesn’t look Blynk related at all, but more of an Arduino thing. It may be best to handle it in a PM instead of here on the forum where it’s possibly quite off-topic :wink: