Mac OS X: How to start up in Single-User or Verbose Mode

You can use a key combination when starting up the computer to enter single-user mode or verbose mode, either of which may be used for troubleshooting and in software development.

Steps to Enter Single-User or Verbose Mode

1. Shut down the computer if it is on.
2. Press the power button to start the computer.
3. Immediately press and hold the Command (Apple) key and one of the following:
• the "s" key for single-user mode.
• the "v" key for verbose mode.
4. To exit single-user mode type: reboot
5. Press Return.

You have successfully entered single-user or verbose mode when you see white text appear on the screen.

Notes

1. If you do not develop software, verbose and single-user modes are only needed when troubleshooting the computer for a startup issue.

2. You cannot enter single user or verbose mode if the computer owner or administrator has enabled Open Firmware Password Protection.

3. When in single-user or verbose mode, the keyboard layout is US English.