I've stumbled upon an issue and I don't have any idea yet about how to solve it. The problem is as follows:
I have a sketch which connects to a database using an ethernet shield and sends some data. The problem is that after I upload the sketch everything works, but if I disconnect the arduino from the computer and power it from another source. Nothing happens, I don't get anything sent to the database. If I recconect it to the computer, open the IDE and open the Serial monitor, the Arduino starts sending data to the database.
My first reaction was to get rid of all the serial.print's, and serial.begin ... but the problem persists...