Arduino Uno can't upload program

Development Tools IDE 1.x
6
  1. Does COM1 disappear when you disconnect the board?
  2. Are there any new devices (e.g. unknown) showing anywhere in Windows device manager when you connect the board.

You probably need a driver but you need to identify the TTL-to-USB chip (the chip closest to the USB port) to know which one. Either try to read it (take sharp photo, enlarge) or check the VID and the PID in Windows device manager for the unknown device (right click, properties, details tab, Hardware Ids from the dropdown box).

If (!!) the chip is the CH340 (the most common one on clones), you can download the driver from CH341SER.ZIP - NanjingQinhengMicroelectronics, extract it and run the exe to install the driver.