Multiple nis.exe with Norton Internet Security

I frequently have 3 nis.exe running. If I look under Windows Task Manager/Processes, none of them have anything under User Name, it's blank. Under services, it shows just one of them. I get two icons on the task bar. It doesn't always happen. Isn't the normal state to have 2. One System and the other User. I have only one user logged on. Anyone know how to fix this.