RobotC for RCX cannot find USB IR Tower I have looked for similar question but found null. So here I am asking.

I have Win7, a RobotC fo RCX and Mindstorms for RCX (both are old version, but available free). I borrowed an old LEGO kit (9794 Team Challenge) which lacked some parts. It has RCX 1.0 as controller. I borrowed a USB IR Tower from my friend.

After a well installation, I tried RobotC and was asked to download firmware to RCX brick.
But RobotC cannot communicate with it because it cannot find the port which I plugged the IR tower to. Inside the preference, there are two available USB port recognized.

I swithced between them but RobotC still cannot find the tower. I have been googling this around for almost a month now.

Thanks for any enlightement.
If you are you using ROBOTC 2 for RCX you need to install the separate driver for windows 32bit.  This driver is not included in the ROBOTC install (at least not with version 2.03).

It might also be a good thing to start with a fresh install of ROBOTC 2.03.