Don -
If you go into the html user's guide that was installed when you installed the software and then go down to product information, you should see a subheading for lights. It should give you a chart of what the codes mean. Mine for the 4870 doesn't show any orange lights (just red), so things must have changed with the 4990.
Are you using a known good port and USB cable? USB port problems or a bad cable can cause the communication error (so can a DOA scanner, but we are trying to be positive here!). You might try another know cable. Also, you might want to try a known good firewire cable and port just to be sure you have covered all your bases.
Doug
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