Delete Sundren.state and Sundren.ver in the My documents\Neverwinter Nights 2 folder and run the updater again. I was just dealing with a similar problem myself
Check FAQ, you would have found this troubleshooting suggestion
The very existence of flame-throwers proves that some time, somewhere, someone said to themselves, You know, I want to set those people over there on fire, but I'm just not close enough to get the job done.
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