System Integrity Protection is a security technology in OS X El Capitan and later that’s designed to help prevent potentially malicious software from modifying protected files and folders on your Mac. System Integrity Protection restricts the root user account and limits the actions that the root user can perform on protected parts of the Mac operating system.

Further reading: https://support.apple.com/en-us/HT204899

How to fix it

macOS 10.11 – 10.14

  1. Boot to Recovery OS by restarting your machine and holding down the Command and R keys at startup.
  2. Launch Terminal from the Utilities menu.
  3. Enter the following command:$ csrutil enable
  4. Then restart you Mac again and run SimpleumCheck to check this again.

Keep in mind: not every security and privacy setting is suitable for everyone. Enhancing the security can lead in losing functionality and/or comfort.
Before making changes, please backup your Mac! Do not make too many change at once. After changing your Mac, check if your normal usage of your Mac has changed in a way which fits to you. Are your really willing to loose some functionality and/or comfort?
Most important is, that you learn and understand what are the advantages and disadvantages of the security settings and that you are aware about the capabilities and risks of your Mac configuration.

To skip this result message from your next security scan, you can deactivate this check. FAQ: How to deactivate a check.

CHECK RESULTS BY SIMPLEUMCHECK DO NOT COVER ALL ASPECTS OF POSSIBLE SECURITY CHECKS OR MAYBE INCORRECT OR INCOMPLETE. THE RESULTS ARE ONLY CLUES FOR RECOMMENDATIONS TO IMPROVE SECURITY AND PRIVACY ON THE MAC.

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