The n32userl.dll file is a required component of Norton AntiVirus. If you are using Norton AntiVirus, then you do not want to terminate or remove.
The n32userl.dll file is not a security risk. If the file is causing problems, then you will want to run a registry cleaner. It is important to run a registry cleaner instead of trying to resolve it yourself. If you are not 100% sure of what you are doing, then you can make things worse. This is why ZookaWare made ZookaWare PC Cleaner.
ZookaWare PC Cleaner is a top notch registry cleaner. It will scan your computer for registry errors and will remove 100% of them. If you are not satisfied with the results, then ZookaWare will give you your money back.