Charles wrote:
> I'm trying to use an appliance that connects to an RS232
> serial port on newer PCs without serial ports by using
> a USB->Serial adapter under Windows XP SP2.
>
> The (older) software which operates the appliance is
> programmed only to connect to a serial port COM1 to COM4,
> but on some PCs the adapter driver installs as a higher
> port, e.g., COM5.
>
> If I check the advanced properties of that port with a
> view towards changing it, I find that the lower ports
> are all listed as "in use". However there's nothing in
> the Device Manager under COM ports to indicate what is
> using them.
>
> How can I determine what is using those ports? Would it
> be possible to reassign whatever it is to a higher
> numbered port so as to free up a port in the COM1-4 range?
>
> Thanks for your help.
Try this free utility: ComCheck32 at bottom of this page.
http://www.addenda-elect.com/software.htm
Not sure if it pertains to your problem.