Check this thread

https://www-secure.symantec.com/connect/forums/different-virus-cleanup-resolution-steps-and-tools

Security Best Practice Recommendations

http://www.symantec.com/docs/TECH91705

Best practices for responding to active threats on a network

http://www.symantec.com/docs/TECH122466

Security Response recommendations for Symantec Endpoint Protection settings

http://www.symantec.com/docs/TECH122943

Best Practice when Symantec Endpoint Protection or Symantec AntiVirus is Detecting a File that is Believed to be Safe

http://www.symantec.com/docs/TECH98360

https://www-secure.symantec.com/connect/forums/your-system-infected-symantec-tools-help-clear-infection

Check this thread

http://www.symantec.com/connect/forums/virus-cleanup-exercise

Hi,

You can use risk reports to find out if any new virus infected in the network.

Go to the Reports tab, Select Report type as a 'Risk',  then under Selected report choose 'New risk detected in the network'.

If you believe there is a new threat in the network & Symantec is not detecting it then please run Sep support tool & submit the suspicious files to the Symantec for further analysis.

Here is the location of the Symantec Endpoint Protection Support Tool:

http://www.symantec.com/business/support/index?pag...

Make sure all the machines have latest definitions.

Windows machines should have latest patches/Service pack.

Disable autorun.

Refer these articles as well.

Security Best Practice Recommendations

http://www.symantec.com/docs/TECH91705

Best practices for responding to active threats on a network

http://www.symantec.com/docs/TECH122466

Security Response recommendations for Symantec Endpoint Protection settings

http://www.symantec.com/docs/TECH122943

User Risk Tracer

How to use Risk Tracer to locate the source of a threat in Symantec Endpoint Protection

http://www.symantec.com/business/support/index?pag...

What is Risk Tracer?

http://www.symantec.com/business/support/index?pag...

About Risk Tracer

http://www.symantec.com/business/support/index?pag...