macOS
Mac does not detect an external display
Check display input, cable capability, adapter limits and macOS detection before replacing hardware.
Category
macOS
Display, storage, update and peripheral troubleshooting for Mac computers.
Diagnose
Error fixes
macOS
Mac starts with a flashing question mark
Respond to a flashing folder by checking startup disk visibility and recovery options.
macOS
Mac says USB Accessories Disabled
Reduce USB power demand and identify the cable, hub or device causing an accessory-disabled warning.
macOS
Mac Wi-Fi connects but websites do not load
Check DNS, VPN, captive portal and network settings when a Mac has Wi-Fi but no browsing.
macOS
Mac Bluetooth is unavailable
Restore a missing Bluetooth service by checking restart, peripherals, macOS and hardware state.
macOS
Mac System Data uses excessive storage
Investigate large System Data without deleting unknown library or system files.
macOS
MacBook battery is not charging
Check adapter power, optimized charging, port condition and battery service status.
macOS
macOS update is stuck on installation
Recover a stalled macOS update while preserving power, storage and data.
Maintain and recover
Guides
macOS
How to start a Mac in Safe Mode
Use the correct Intel or Apple silicon startup method to test extensions and caches.
macOS
How to verify a Time Machine backup
Confirm that backups are current, readable and independent before repair or upgrade.
macOS
How to run Disk Utility First Aid
Choose the correct container and volume order and understand when First Aid is not enough.
macOS
How to format an external drive for Mac and Windows
Choose exFAT, APFS or another file system based on compatibility and backup needs.
macOS
How to collect Mac system information for support
Gather useful model, software and diagnostic details without sharing serial numbers or private data publicly.