Safe mode is a way to compare behaviour with a different startup environment. It can help investigate software loaded during startup, but a successful safe-mode boot is not a certificate that every hardware component is healthy.

Choose the instructions for your Mac

Check About This Mac. An entry labelled Chip identifies Apple silicon; an Intel processor entry identifies an Intel-based Mac. Save open work before shutting down or restarting.

For Apple silicon, shut down completely, then hold the power button until startup options appear. Select the startup volume, hold Shift and choose Continue in Safe Mode. For Intel, turn on or restart and immediately hold Shift until the login window appears.

Apple notes that Safe Boot appears in the login-window menu bar. If uncertain, open System Information, select Software and inspect Boot Mode. Confirm the environment before using the result to make a troubleshooting decision.

Repeat one defined task

Try the shortest safe sequence that normally produces the problem. Record whether it still occurs and whether any required feature is unavailable in this environment. A task that cannot be performed is not the same as a task that passed.

Restart normally and repeat the comparison. Keep the application version, test file and connected accessories consistent where practical. Changing several variables at once makes an apparent improvement difficult to interpret.

If the issue changes in safe mode, use that observation to guide a review of startup software and related configuration. Do not immediately delete every login item or reinstall the operating system.

If the computer shows physical damage, liquid exposure or unstable storage, stop and address those risks first. Repeated startup experiments are not a substitute for a data-protection plan. Share the observed normal-versus-safe behaviour when requesting help; it is more useful than saying simply that safe mode “fixed” the Mac.

Source: Apple's safe-mode instructions.

For help with your Mac, contact AEPC in East Auckland or call 027 908 8880 to discuss your requirements.