In this you will get the configuration of forefront client security antivirus definitions automatic updates for server and clients

To doing this go to the WSUS updates services in Server manager of System Center essential 2010 server

Then choose Automatic Approvals from the options of WSUS services there you have to create new rule select “When an update is in a specific classification” in Step 1

Under that you can see in Step 2 edit the properties of above click the link and ” you will get all classification you can choose critical updates,Definition updates,Service packs,Security updates”

Below you can set the approval for clients,Servers,un assigned computers