We're still on SEP 12.1.6. I see 12.1.6_MP3 is out. We're waiting for things to settle down.
Meanwhile I've got a Mac that had SEP 12.1.6 on it. It was upgraded to El Capitan. Later I came back to it, thought there was no SEP on it and use something else since it was El Capitan. Today I see it's got SEP there, so I uninstalled the other antivirus program. Going into SEP on it now, some things are disabled... It would get updates but said it wasn't updated, wouldn't do a full scan...
So I downloaded Symantec_Endpoint_Protection_12.1.6_MP3_All_Clients_EN.zip. Unzipped, installed. Everything looks green and happy on the Mac now.
When we install and upgrade, we just use the SEPM installer, upgrade the Symantec server, and generate Win and Mac installers from there (or just push out upgrades from SEPM).
I'm thinking instead of doing another SEPM upgrade and upgrading all the clients, I might just used the 12.1.6_MP3 for fresh El Capitan installs. (Otherwise, I could install to Lion/Yosemite/whatever it came with restored, install our plain 12.1.6, and then upgrade to El Capitan. That way SEP is on there.)
If I use the "freestanding" Symantec_Endpoint_Protection_12.1.6_MP3_All_Clients_EN.zip though on a fresh machine.... How does it know to connect to our SEPM server though? That's what I'm wondering. Is there a config file or something simple I can do on the fresh/freestanding-install client machine to direct/add it to our SEPM server collection?