It seems you've reinstalled NIS after a clean boot & it still will not work. Is this correct? Do the other options work OK? Does this happen even after installing all the NIS updates - not just the automatic ones? Do you have all the Windows updates installed correctly? To check this you could install & run Belarc - click here. Is your PC free of ad/spyware? Which version of NIS are you using?
I'm on NIS 2003 & Win98se too, & all works fine.