My federal return was rejected. Customer service messages: "none"

I efiled my federal return today, and it was rejected.  When I click "Show Message", it gives me a dialog called "Customer Service Messages", and the only contents are the time, the date, and the word "none."  When I clicked "Help Me Fix It", it took me straight to "Let's Re-file Your Return."  How can I find out what the actual problem was?