How to join a Microsoft Active Directory Domain with Lion OS X

System Preferences > Users & Groups > Click on 'Login Options' > then click 'Join' button next to where it says "Network Account Server".

Then the dialog box that comes down allows you to enter the AD domain server there. Click Ok.

How to restore an iPhone, iPad, or iPod without a passcode

iOS: Unable to update or restore

Summary

You may experience one of the issues listed below with your iPhone, iPad, or iPod touch when you attempt to update or restore. If any of these occurs, you can place the device into recovery mode and attempt to restore the device again.

Products Affected

iPad, iPhone, iPod touch

• Device continually restarts but never displays the Home screen.
• An update or restore did not complete and the device is no longer recognized in iTunes.
• Stops responding, showing the Apple logo with no progress bar or a stopped progress bar, for over ten minutes.

Notes:

• In certain situations, an iPhone, iPad, or iPod touch will automatically go into recovery mode after an update or restore issue. If your device is already in recovery mode, you can attempt to restore using iTunes.
• If iTunes displays an alert with an error code, see this article before attempting the steps outlined here.

Placing your device into recovery mode

Follow these steps to place your iOS device into recovery mode. If your iOS device is already in recovery mode, you can proceed immediately to step 6.

1. Disconnect the USB cable from the iPhone, iPad, or iPod touch, but leave the other end of the cable connected to your computer's USB port.
2. Turn off the device: Press and hold the Sleep/Wake button for a few seconds until the red slider appears, then slide the slider. Wait for the device to turn off.
   • If you cannot turn off the device using the slider, press and hold the Sleep/Wake and Home buttons at the same time. When the device turns off, release the Sleep/Wake and Home buttons.
3. While pressing and holding the Home button, reconnect the USB cable to the device. The device should turn on.
   Note: If you see the screen pictured below, let the device charge for at least ten minutes to ensure that the battery has some charge, and then start with step 2 again.
   
4. Continue holding the Home button until you see the "Connect to iTunes" screen. When this screen appears you can release the Home button:
   
5. If necessary, open iTunes. You should see the following "recovery mode" alert:
   
   
6. Use iTunes to restore the device.