Data Load Error with Ultimate Traffic

Can someone please help. I've already tried the UT tech support team but they can't think of any other solutions. UT works fine for me but when I tried to install updates I get the message "DATA LOAD ERROR Ultimate Traffic has encountered a problem while trying to load AirportAssignments.dat file and needs to close." I've used the updater before in the past with no problems, but since then I know I have installed the FS9 update and XP to service pack 2 if that matters. Anyway, tech support checked my AirportAssignments.dat file and it is fine. They said the only way I should get that message is if I had an empty or corrupt file. Also, they said to disable any antivirus software which I did (Norton's), and I turned off the XP firewall. I don't know what else to do.:-hmmm Thanks. Tom