Hello,
My laptop (a Lenovo T420 ThinkPad with Windows 7 32 bit) does not recognise my Arduino Mega 2560. There is, however, a blinking red light and a constant red light. I am using a cable to connect the Arduino to an USB port, however no matter which USB port I plug it in, (ones on the left, the back, the front) it always shows up as an USB2.0 Serial under "Other Devices" with a yellow triangle with an ! over the icon, and when I try to install the driver software, pointing it to the arduino\drivers directory, Windows reports that it cannot find any drivers for the software. In the Arduino programming software, I have tried uploading to COM3 and COM4, however neither of these work. I have also tried using my desktop, however it has the same problem. If anyone has any suggestions what to do, or if I need to provide any more information/screenshots, please tell me! (I have tried googling the problem and following their suggestions, but that hasn't worked.)