The Symantec Endpoint Protection (SEP) installer or other Symantec tools fail to run on macOS 10.12 "Sierra" or later.

You may see one of the following errors:

• Installation Failed
• Symantec Endpoint Protection has failed to install
• The application "Symantec Endpoint Protection Installer" can't be opened.

See Additional Information for a full list of related errors.

• Symantec Endpoint Protection
• macOS 10.12 "Sierra" or newer

These errors may be caused by a macOS security feature that assigns extended attributes ("com.apple.quarantine") to any file that has been downloaded from a network site or has been moved from its original download location ("App Translocation").

Other circumstances may have altered macOS file attributes or permissions settings.

Possible causes of these symptoms:

• The installer was downloaded from a network location
• The file was moved from its original download location
• The zip archive was decompressed on a different file system (i.e. Windows) before copying it to Mac

Reset the extended attributes and permission settings for the affected files.

For example, for "Symantec Endpoint Protection Installer" and "Additional Resources" in "SEP" folder of the user's desktop, open a Terminal window and run the following commands:

sudo xattr -rc "~/Desktop/SEP"
sudo chmod -R 755 "~/Desktop/SEP"

Next, retry the installer or tool.

Note: If the above path syntax does not work, try using the "cd" command to navigate to the appropriate parent folder (remove quotes for folder names that do not contain spaces) before trying the commands.

For example:

sudo xattr -rc <parent folder name>

See the full list of potential errors below:

• Installation Failed
  Your installer is either corrupt or missing important resources.
   Please try again later or contact Support.
  
  
• Symantec Endpoint Protection has failed to install
  The installer encountered an error that caused the installation to fail
  Contact your IT Administrator for assistance
  
  
• "The application "Symantec Endpoint Protection Installer" can't be opened."
  
  
• "... cannot be opened because it is from an unidentified developer ...
      macOS cannot verify that this app is free from malware."
   
• "Install Failed: Invalid Symantec Endpoint Protection Package ...
      Please make sure latest package is downloaded to /Users/[username]/Downloads"
  
  
• "It seems like something went wrong with the installation of the product"
   
• When using the Installer's Tools menu->Create remote deployment package:
  "Remote deployment package creation closing ...
      Error creating package. Refer to console log for details."
  
  
• The file "RemoveSymantecMacFiles.command" could not be executed because you do not have appropriate access privileges.
  To view or change access privileges, select the file in the Finder and choose File > Get info.