I purchased a Rosewill RC-301 "2 Port Serial PCI Adapter" for my desktop computer which is running Win 7. It works without a hitch unless you are actually running another program which uses the com port.
Below, I've inserted a quote from a Q&A response which used to be on the URC website.
"My MX-Editor software and remote are not communicating. What do I do? Typically, there are a few reasons for this problem. The number one problem we have found is the use of Active Sync or Hot Sync software that is holding on to the active com ports and preventing your PC from communicating with the MX-700. Some digital camera software or software for wireless docking stations, keyboards, or mice can also prevent communication with your MX-800. You may have to disable or even remove the software that is blocking communication with your MX-800. Alternately, the MX-Editor and computer port may not be set to communicate properly, or you may have a bad cable connection.
Here is the best way to check to see if your settings are correct: 1.In MX-Editor click "COMMUNICATIONS" 2.Click "SETTINGS" 3.Write down the COM PORT NUMBER 4.Go to your Windows Device Manager (Usually found under "Control Panel", "System", then the "Hardware" tab) 5.Click the "+" next to "PORTS" 6.Find the port that has "(COM ...)" at the end of it and make sure it matches the COM Port number you wrote down in step 3 7.If the number matches, right click on that port and select "PROPERTIES" 8.Select the "PORT SETTINGS" tab 9.The settings should read as follows:
Bits per second: 9600 Data bits: 8 Parity: None Stop bits: 1 Flow Control: None Click "ADVANCED" Make sure "Use FIFO buffers..." is CHECKED Make sure both sliders for "RECEIVE BUFFERS" and "TRANSMIT BUFFERS" are all the way to the right Make sure the "COM PORT NUMBER" matches the Com Port you wrote down in step 3 Click "OK" until you have closed the Device Manager and Control Panel 10.Reopen the MX-Editor software and test it by attempting to do a download to the remote (Full Download) "
