Hmmm.. Let's start here:
http://arduino-info.wikispaces.com/GettingStarted-Software Off to:
http://arduino.cc/en/Guide/WindowsHHmmm.. I THINK that IF you have a Arduino UNO (Which board do you have)?? That windows7 does not need any added drivers.
Can someone else confirm this??? I'll update my docs...
Please read the TroubleShooting Guide here:
http://www.arduino.cc/en/Guide/Troubleshooting---------------------( COPY )--------------------------
On Windows 7 (particularly the 64-bit version), you might need to go into the Device Manager and update the drivers for the Uno or Mega 2560. Just right click on the device (the board should be connected to your computer), and point Windows at the appropriate .inf file again. The .inf is in the drivers/ directory of the Arduino software (not in the FTDI USB Drivers sub-directory of it).
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