Rosetta may block the Mac client installation on Apple Silicon (M1) devices with the following error:
"Installation Failed - This version of Symantec Agent for Mac is not supported on Apple M1 chip."
"Installation Failed - Your installer is not working properly. Please contact Support."
SEP 14.3 RU2 and newer is compatible with the M1 chip and does not require Rosetta, but the installer in RU2 still checks for it. This check is removed in 14.3 RU3.
This error may also occur if "Open using Rosetta" is enabled in general properties of SEP installer or the SEP application itself.
Symantec Endpoint Protection client for Mac 14.3 RU2 and later
Use SEP for Mac version 14.3 RU3 or newer.