Step 1: Symantec 12 for Mac requires a Mac desktop or laptop running Mac OS 10.5 or higher with an Intel processor and a minimum of 512 MB of RAM. To find your system specifications, click on the Apple menu in the upper-left corner of the screen then choose About This Mac. Your computer\’s information will be displayed.
For Mountain Lion (10.8) Only:
Step I: Open System Preferences and click on Security & Privacy. On the bottom left, click the lock and enter your user credentials.
Step III: Select the newly unlocked option of “Anywhere” under the “Allow applications downloaded from:”. This will allow you to proceed successfully.
For all versions of OSX:
Step 4: In the pop-up window, select “Symantec Antivirus V12 -Mac”. Click “Continue” once you’ve made your selection.
Step 7: After downloading and extractiong the ZIP file, double click the Symantec Endpoint Protection.mpkg icon to begin the installation.
Step 15: When the installation is complete, click Log Out. Your computer will log you out of your account.
Step 16: When prompted, log back in to your account. The Symantec LiveUpdate window will open automatically and begin downloading updates. This may take several minutes to complete.
Step 17: Installation and updates are complete. Symantec Endpoint Protection is configured to update update automatically and without user intervention. The software will perform a virus scan daily at 8 p.m. and will update virus definitions hourly. Once the updates have been installed, you will see a summary window listing the updates. Click Quit to dismiss the window.