Arduino is detected as a device (see the image). But in Arduino IDE or my own program which lists all available serial ports it is not listed. There is COM3, but it obviously is the native COM3 - because the programs does not communicate with Arduino.
I have PC with 7 native serial ports with Windows 7 32 bit running on it. I installed Arduino IDE 1.0.5 with the USB/serial driver. When I plug in Arduino Uno new COM port is added in device manager "Arduino(COM3)". But there is already native COM3! No program, not even Arduino IDE, is able to communicate with Arduino. No new COM port is listed. That same Arduino and IDE works perfectly on a laptop without native serial ports. I cannot communicate with Arduino on this PC at all ! Is there a way to solve it?
I have windows XP, SP3. I thought there is a driver problem, but anything I did with the drivers didn't help. I was desperate and I tried older version of Arduino IDE and uploading was working smoothly. More info about the problem: when I click upload button in IDE rev 1.0, the progress bar gets filled for ~ 80% and than the program hangs. It's not possible to open the serial port any more. There is a deadlocked process "avrdude". If I kill it, IDE is responsing again and serial port is accessible.
In my project I have stabilized 5V power supply to power Arduino Mega 2560. May I connect it to +5V pin ? Will it not damage Arduino builtin stabilizer, or will not the stabilizer take some (significant) current ?