This error appears when you try to install Norton Security on Mac OS X 10.7.4 or earlier. Norton Security for Mac provided by Symantec Endpoint Protection Small Business Edition Cloud (SEP SBE.Cloud) can be installed only on Mac OS X 10.8 or later.
You can't use this version of the application Install Norton Security with this version of Mac OS X.
Apple allows any user running Mac OS X 10.6.8 or later to upgrade their OS for free via the Mac App Store. For further information on hardware compatibility of Mac models with newer versions of macOS, refer the macOS Support website.
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