When migrating endpoints from version 12.x or early 14.0 iterations to version 14.2, follow an ordered upgrade path:
macOS 10.12 up to the maximum certified version for the specific 14.2 point release. Requires 2 GB RAM and 1 GB disk space. Symantec Endpoint Protection 14-2 Download
: Intel Xeon or AMD Opteron minimum (2 GHz or faster recommended). When migrating endpoints from version 12
Roll out the client upgrade packages in controlled phases across your production groups to prevent network congestion. Symantec Endpoint Protection 14-2 Download
Quick Start for Symantec Endpoint Protection - Broadcom TechDocs