Mac iBook / PowerBook won't sleep when closed?

You're not the first person to encounter this sort of problem with a laptop, but have faith, there are a number of standard paths you can travel to find a solution to this problem.

Here are the four top possible solutions to fix your sleepless, insomniac iBook, according to Apple:

1. Check your Energy Saver preferences to make sure that you've allowed your Mac to sleep: From the Apple menu, choose System Preferences. Click Energy Saver, then click the Sleep tab. Make sure that the two sliders are not set to "Never" sleep.
2. If DVD Player is the active application, your computer won't go to sleep even when it's left idle. Either switch to another application or quit DVD Player.
3. If you're using an iBook or PowerBook that won't sleep when you close its lid, make sure that the keyboard is seated properly. If the lid presses a key when it's closed, it will prevent your computer from sleeping.
4. If you're using a Mac OS that's older than Mac OS X 10.3 Panther, turn off the faxing option. From the Apple menu, choose System Preferences. Click Print & Fax, then click the Faxing tab. Deselect the "Receive faxes on this computer" checkbox.

If none of those do the trick, you can try reseting some of the NVRAM (non-volatile RAM) settings by doing this:

1. reboot while holding option-command-o-f (boot into open firmware)
2. type reset-nvram
3. type reset-all
4. reboot the iBook

Still hasn't fixed it? Check out the Mac OS X Hints Forum: iBook and Sleeping.

Good luck!