Mac does not detect an external display
Check display input, cable capability, adapter limits and macOS detection before replacing hardware.
macOS
Mac notebooks, desktops, displays and macOS peripherals.
Published resources
Check display input, cable capability, adapter limits and macOS detection before replacing hardware.
Respond to a flashing folder by checking startup disk visibility and recovery options.
Reduce USB power demand and identify the cable, hub or device causing an accessory-disabled warning.
Check DNS, VPN, captive portal and network settings when a Mac has Wi-Fi but no browsing.
Restore a missing Bluetooth service by checking restart, peripherals, macOS and hardware state.
Investigate large System Data without deleting unknown library or system files.
Check adapter power, optimized charging, port condition and battery service status.
Recover a stalled macOS update while preserving power, storage and data.