If you have one computer one which the remotes are working correctly and one on which they are not, you can use the first computer to diagnose the issues on the second by replacing each component in turn until you find out which component is not working:
1) Check the remote control
a) Take the remote control from the computer that it is not working
b) Go to the computer where everything is working
c) In the scoreboard application, go to the remote control configuration settings page
d) Put the cursor in the remote serial number textbox and click any button on the remote control
If the serial number appears in the box, then you have confirmed that the remote is working correctly. If it does not, the remote is faulty.
2) Check the receiver
a) Take the receiver from the computer that is not working (excluding all cables)
b) Unplug the receiver from all the cables on the computer that is working
c) Plug the receiver from the computer that is not working into the cables on the computer that is working
d) Test to see if the remote is still working
If the remote is no longer working, then the receiver is the problem.
3) Check the power cable to the receiver
a) Take the receiver power cable from the computer that is not working (excluding all cables)
b) Swap the receiver power cable on the computer that is working for the receiver power cable from the computer that is not working
c) Test to see if the remote is still working
If the remote is no longer working then the receiver power cable is the problem.
4) Check the receiver serial cable
a) Take the receiver serial cable from the computer that is not working (excluding the serial to USB adapter if one is being used)
b) Swap the receiver serial cable on the computer that is working with the receiver serial cable from the computer that is not working
c) Test to see if the remote is still working
If the remote is no longer working then the receiver serial cable is the problem.
5) Check the USB to serial adapter (if one is being used)
a) Take the USB to serial adapter from the computer that is not working
b) Swap the USB to serial adapter on the computer that is working with the USB to serial adapter from the computer that is not working
c) Test to see if the remote is still working
If the remote is no longer working then the USB to serial adapter is the problem.
If you have performed all the steps above an the remote still works in all instances then the issue is not with any of the hardware, but instead lies with the computer itself. To test the computer, take all the components from a known working computer and plug them in to the problematic computer. Ensure that the drivers for the USB to serial cable have been installed correctly, and make sure that the correct port has been selected in the remote control configuration page of the configuration settings. If the problem still persists, check the event log on the promblematic computer for any error events which may hint at what the problem is.
You can also download the comporttester application from here:
http://www.spawtz.com/SpawtzScorer/CommPortTester.exe
And use that to see if remote button presses are actually being read correctly by the computer. You must close down the scoreboard application before running the comporttester application, but once you have, you can open the test application and one by one select each com port from the drop down list and then click "Connect". If a connection is established, click any button on the remote control. If button presses are correctly being registered, a load of text will appear in the comporttester window. You can use this tool to determine which com port the receiver is actually residing on.
If you are still unable to configure the application correctly it suggests there is an issue with the actual computer hardware. You will need to get a hardware technician to ensure that the computer is functioning correctly.