I tested with the same installation, IR tower & rcx module with another laptop (by Dell) built with infrared port, wireless network card, but with no bluetooth built in. They work fine... The problem is more and more leaning over to hardware (...) (21 years ago, 17-Oct-03, to lugnet.robotics.rcx.robolab)
I may be stepping out on a limb, but have you tried reformatting the laptop that doesn't work? What about using NQC or the original Lego software to test and make sure its not RoboLab in combination with your laptop that is causing errors. Ok, (...) (21 years ago, 17-Oct-03, to lugnet.robotics.rcx.robolab)