SymProxySvc.exe is a part of Norton Internet Security. More information can be found here.

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Symantec's Norton Internet Security 2005 provides essential protection from viruses, hackers, and privacy threats. Norton AntiVirus is the world?s most trusted antivirus solution.* Norton Personal Firewall keeps personal data in and hackers out. And Norton Privacy Control, Norton AntiSpam, and Norton Parental Control safeguard you and your family from other common online risks.