What is it?
Norton AV - navshext.dll

What does it do?
This file is a part of Norton AV. There is a common error while trying to uninstall Norton where this file fails to be removed. Their support page on this matter can be found here. You'll see a message that says: "Cannot delete navshext.dll. The specified file is being used by Windows." This happens even if the computer has been restarted in a clean boot or in Safe mode. The best fix is to unregister this .dll file and then delete the folder.

Virus Precautions:
You'll want to keep an eye on this google search for any known viruses. The normal location of this file is C:Program FilesNorton AntiVirusNavShExt.dll


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