You want to know how stopping SMC will affect the Symantec Endpoint Protection (SEP) client.

Issuing the smc -stop command stops the Symantec Management Client (SMC) and the Symantec Endpoint Protection service (ccSvcHst.exe).

For example:

C:\Program Files (x86)\Symantec\Symantec Endpoint Protection\smc.exe -stop

Stopping SMC disables the following features in all versions of SEP:

• Client-Server communications
• Automatic content updates
• Client notifications
• Network Threat Protection (NTP) Firewall, and all traffic will be allowed unless "Block all traffic until the firewalls starts and after the firewall stops" is enabled in SEP security settings,
• Client Intrusion Detection System (CIDS)
• Application and Device Control
• Host Integrity

Stopping SMC disables the following features in SEP 14 and newer. In SEP 12.1.x these features are still enabled but no client notifications will be generated.

• Auto-Protect
• Proactive Threat Protection: SONAR and Device Control
• Download Insight
• Email Auto-Protect

In all versions of SEP when SMC is stopped the following feature is still enabled but no client notifications will be generated.

• Tamper Protection

To restart SMC use -start command line:

C:\Program Files (x86)\Symantec\Symantec Endpoint Protection\smc.exe -start