Arduino IDE and Drivers Installation (Windows XP)
Arduino UNO and Arduino Mega Software and Drivers Installation
This tutorial describes the installation of the Arduino IDE Development software and drivers for the Windows Operating System. The images and description is based on installation under Windows XP, but the process should be similar for Vista and Windows 7.
First we need to get the latest version of the Arduino software this can be downloaded from the Arduino website here
Download the Arduino software and unzip all the files into c:\program files
You will end up with a directory like arduino-0021 or similar
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One final note. Create a shortcut to the Arduino IDE and place it on your desktop |
Next, plug in your Arduino board to your computer with a USB cable and wait while Windows detects the new device. 
Now choose the location that the Arduino drivers are stored in. This will be in a subfolder called drivers in your arduino directory
After selecting Next you may get a message like the one shown right. 
Windows should now have found the Arduino drivers. Click Finish to complete the installation
So far so good. The computer communicates with the Arduino board via a special serial port chip built into the Arduino board. The Arduino IDE software needs to know the serial port number that Windows has just allocated to it
Next, run the Arduino IDE application, which will be in c:\program files\arduino-0021 or similar
Next click on Tools | Board and select the type of board that you have
Thats it. Now try opening the Blink demo program from the example directory within the Arduino IDE, Verify/Compile it and upload it to your board. You should see the TX and RX leds on the board flash showing you that it is working.