Perhaps one of your configuration files is corrupt, usually the main setup.dat file. Try moving all of the .dat files out of the configuration data directory and run NL again. If there error goes away then it was one of those files. You could move a few of the files back in until you find the corrupt file.
You can find the location and explanation of each configuration file at http://www.newsleecher.com/forum/viewtopic.php?t=6766
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It isn't God I have a problem with. It is his fan club I cannot stand.