The cause is not there. But it's new so you can make it a warranty issue.
Me and my wife have identical machines. They are custom built and both run XP SP2.
On my machine I have a diabetes monitor on com 1 and a blood pressure monitor on com 2. Both pieces of equipment work fine on my machine. My wife just got the same equipment as me and I connected them to the com ports on her machine. None of the equipment is found when we try to use them. I checked to make sure that the ports are enabled and they are. The settings on hers are the same as mine. I connected her equipment to my computer and they work fine. I can't seem to figure out what is wrong. Can anyone help?