Mac won't sleep when connected to apple monitor in clamshell mode

[tman1425]

My Macbook Pro would always go to sleep automatically after 30 minutes. However, once I connected it to the apple monitor and used the computer in clamshell mode, it won't go to sleep unless I do it manually.

Does anyone know why automatically sleep anymore? The apple monitor turns off, but the computer doesn't sleep. None of the setting have been changed either. Any help is appreciated. Thanks in advance.

 

[GGJstudios]

Mac OS X: Why your Mac might not sleep or stay in sleep mode

 

[tman1425]

Mac OS X: Why your Mac might not sleep or stay in sleep mode

I've already seen that. No settings have changed, no programs are running, etc. The only difference is being connected to an external apple display...

 

[tman1425]

One last bump to the top. Anyone have any suggestions?

 

[kylepdx]

One last bump to the top. Anyone have any suggestions?

I understand, same problem here. I did not have the problem and have not made any changes and have not added any software or changes any utilities. This started happening with my laptop after upgrading to LION.

It will go to sleep if you disconnect the power AND the Cinema monitor. Otherwise I can not back to the normal sleep after 30 minutes no activity. And disconnecting the power and monitor each time I use it...SUCKS!

 

[Frank (Atlanta)]

I, too, am suddenly having this problem. Don't believe any settings have been changed and my MBP was able to automatically go to sleep previously...

 

[Frank (Atlanta)]

Found my problem… I had a Garmin ANT+ Agent that wouldn't let my machine sleep. If I disable it, all is fine.

 

[applesith]

I, too, am suddenly having this problem. Don't believe any settings have been changed and my MBP was able to automatically go to sleep previously...

Same here even when it's just the power is plugged in as well as with monitor.