MacTidyGuide / Mac security settings
Mac security settings worth checking after setup or upgrade
A plain-English guide to FileVault, firewall, updates, sharing, Lockdown Mode, and MacTidy security levels.
Sources checked: support.apple.com, support.apple.com. MacTidy claims on this page are grounded in the local app engine and current preview download notes.
Security settings are easier to use when they are grouped by real-life tradeoff. FileVault and updates are everyday basics. Lockdown Mode is for a narrower threat model. A good guide should say that out loud.
Start with settings almost everyone should use
FileVault protects data at rest. Automatic security updates keep Apple security content current. A screen lock protects the Mac when you step away. These are low-friction settings and make up MacTidy’s Safe level.
Close services you forgot were open
Sharing, Remote Login, screen sharing and remote management are often enabled for a one-time reason and then left on. MacTidy’s recommended Safer level focuses on those forgotten openings and privacy trails before pushing into heavy restrictions.
Use specialist settings deliberately
Lockdown Mode, blocking all incoming connections, outbound firewall prompts, disabling Siri and limiting extensions can be useful, but they can also break workflows. MacTidy marks the highest levels as specialist choices and asks you to read the cost before applying them.
Respect macOS boundaries
Some settings can be changed by an app with admin approval. Some must be changed by you in System Settings. MacTidy separates automatic steps from guided steps and rechecks what macOS allows it to read.
MacTidy workflow. Scan, read the list, untick what you want to keep, then remove selected items. The app is currently distributed as a developer preview DMG, so the download page calls out the signing and notarization status before installation.
Quick checklist
Confirm FileVault and automatic updates.
Review Sharing services.
Read the cost before turning on Lockdown Mode.
Use the recommended level unless your threat model needs more.
FAQ
Which Mac security setting matters most?
FileVault is one of the highest-value basics because it protects the contents of the Mac if the hardware is lost or stolen.
Should everyone turn on Lockdown Mode?
No. Apple describes Lockdown Mode as extra protection for people who may be targeted by sophisticated attacks. It can break normal features.
What is MacTidy’s recommended security level?
Safer. It closes common forgotten openings without pushing most people into specialist restrictions.
Can MacTidy change every security setting?
No. macOS keeps some settings for the user. MacTidy opens the right pane and explains the step when it cannot change a setting itself.