You should restart the computer and check the configuration of definition updates.
Event: Error during using Dynamic Signature Service This monitor returns the number of events when the System Center 2012 Endpoint Protection has encountered an error trying to use the Dynamic Signature Service. This error is likely caused by a network connectivity issue. Event: Real-Time Protection feature error This monitor returns the number of events when the System Center 2012 Endpoint Protection Real-Time Protection feature has encountered an error and failed. Try to restart the following two services: Antimalware engine and NIS engine.
Think of Endpoint Protection as a giant management pack that wraps up all of this functionality and ties it in a bow. Like most of the products in the System Center line, the biggest, most notable, new feature for Endpoint Protection 2012 R2 is native support for the latest and greatest operating systems recently released by Microsoft.
In addition to antimalware configuration, reporting and deployment, Endpoint Protection also allows policy-based configuration of the local operating system firewall; you can open and close ports for specific groups of users based on need, even at certain times. The SP1 version of System Center Endpoint Protection brought native support for Windows 8 and Windows Server 2012.
Event: Malware or other potentially unwanted software detected This monitor returns the number of events when the System Center 2012 Endpoint Protection has detected malware or other potentially unwanted software. To remove the virus manually, in the System Center 2012 Endpoint Protection interface, click Clean Computer.