Testing COM Ports

I have a computer which has an application complaining that it cannot communicate with COM port 1.

the message is something like

Error contacting COM PORT 1

How can i check that the COM is working properly in Windows ( this is a Windows XP comptuer ). The COM has worked fine before, this must be a new problem.

Is there any commands i can send to the COM port or software which i can use to test it.

I am trouble shooting this remotely via remote desktop, so if possible any suggestions which i can do over remote desktop.

Thank you !

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you can go to device manager and delete the com port then rescan for hardware changes, if it is detected then it should be working, make sure that there is no other application is using the com port while your application try to use it

Scroll to Ports, you should see a Communications Port (COM1) there.
Double-click it.  What's the device status?
Click Restore Defaults from the Advanced tab.
Failing that - uninstall and reboot to allow Windows to reinstall it...

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gisvpnAuthor Commented:
thank you...

could i ask if the COM port was disabled in BIOS would windows see it ? Can i check if its disabled in BIOS from windows ?
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windows will not detect it if it is disabled in bios,

a) - Windows 'shouldn't' detect it if it's disabled in BIOS (I have seen some items recognized in Windows even when disabled in BIOS)
b) No, you can't check it from within Windows.  Reboot and press the appropriate key to enter BIOS (F2, F10, DEL, ESC are more common)

If it 'was' working though - I wouldn't think it would be disabled in BIOS..
If you can get access to the machine physically and hook up a null modem cable to it from another machine, you could run LookRS232 and see if the transmission of a specific sequence gets across.  Another alternative is a loopback plug that will take what is transmitted on the send lines and connect it to the receive lines so you get back what is transmitted.  These came with a diagnostic utility for pcs a while back called PC Tools.
gisvpnAuthor Commented:
Hello thank you for your posts.

The problem has been resolved.

I uninstalled COM port 1, restarted the computer and then reinstalled COM port 1 and it now works all good !

thank you all

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