My mac shuts off after typing in my password.

Hello Pkvanmo,

Thanks for using Apple Support Communities.

If you Mac is unexpectedly powering off after trying to login, then I suggest that you boot your computer into safe mode, and try to login. This will prevent anything that's not from Apple from starting up, and can help identify if you have a 3rd party application that is causing it.

Starting up in safe mode

Follow these steps to start up into safe mode.

1. Start or restart your Mac.
2. Immediately after you hear the startup sound, press and hold the Shift key.
3. Release the Shift key when you see the Apple logo appear on the screen.

After the Apple logo appears, it might take longer than usual to reach the login screen or your desktop. This is because your Mac performs a directory check of your startup disk as part of safe mode.

To leave safe mode, restart your computer without pressing any keys during startup.

If an issue doesn't happen in safe mode

If an issue doesn't happen when your Mac is started in safe mode, try restarting again without pressing any keys at startup. If the issue appears to be resolved when you start up normally, it was possibly caused by a cache or a directory issue with your startup disk that safe mode fixed.

If you restart your Mac normally and an issue comes back when you reach your desktop, try disabling any login items that automatically open when you log in.

If your Mac restarts or shuts down in safe mode

If your Mac automatically restarts in safe mode, OS X might have found an issue that it's trying to fix.

Safe mode performs a directory check of your startup disk, similar to what happens when you choose to verify or repair a disk using Disk Utility. If OS X finds an issue, the directory on your startup disk is repaired and your Mac restarts.

If your Mac turns itself off when you start up in safe mode, check the power connection on your Mac to make sure it's plugged in securely at both your Mac and the power outlet. If you're using a MagSafe power adapter, make sure the LED on your power adapter is yellow or green. Then, try starting up in safe mode again.

If your Mac repeatedly restarts or shuts down during safe mode, contact Apple Support, or consult with an Apple Authorized Service Provider or Apple Genius for more help.

Try safe mode if your Mac doesn't finish starting up - Apple Support

Take care.