Norton Internet Security 2004 – NISSHEXT.DLL
Nisshext.dll installs with Norton Internet Security 2004. You'll probably find it in C:\Program Files\Common Files\Symantec Shared\AdBlocking\NISShExt.dll. As the path suggests, this file is used as part of Norton Internet Security's new popup ad blocker. If you have this feature enabled, thsi file will be running all the time. If you don't want it running, it's better to deselect it from your Norton control panel but it can also be removed via WinPatrol. More information can be found at http://www.symantec.com/sabu/nis/nis_pe/.
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