We've been getting this all the time (well, once or twice this year). Program State and RC Mode lights up on the robot controller, and it doesn't reset and it doesn't download -- just stuck inbetween.
Go to
http://www.ifirobotics.com/rc.shtml, download the 2007 RC Master Code (zip, 2-27-2007) Version 15 (scroll all the way to the bottom), and unzip it to someplace convienent.
With the IFI Loader, browse to that location and click on the .BIN file (you have to change the file type to see it). Download it (obviously you have to be cabled properly).
After it finishes downloading you have to download your own .HEX code again and you're back in business!
I think the reason it happens is that we downloaded code but pulled the cable before it finished, making it in that inbetween state of erased old code and incomplete new code. We did the button trick
Michael DiRamio suggested for about an hour until we tried downloading the master code again. Luckily we learned this before Manchester, as it happened there and we didn't have an hour to figure it out.
And because this is in the Electrical Forum, do make sure your wires are all proper.