Sleep mode issue - won't go to sleep

I have the same problem too. I have a 24 inch iMac and the screen will sleep but the hardrive won't unless I manually put it to sleep.

I guess that's one thing apple won't mention in there commercials. Or the fact that my iMac wasn't compatible with any of my external devices. Like my digital camera, printer, router. All of these things that automatically worked with my prehistoric PC took me 10 hours each of internet searching to fix the problems. I never got my printer to work and now it won't sleep.

I never had any problems like this with my PC. Why are Macs better?

I have exactly the same problem, 2008 Mac Pro that will not go to sleep by itself. I have a Macbook with a very similar build and that sleeps no problem. The only major differences are Mozy and Timemachine. I uninstalled Mozy but that did not make a difference. I have been looking for a solution for sometime with no luck!

Same problem here.
No solution yet.

Same problem here. Tried almost everything. Nothing worked.
Maybe a buggy update?

My workaround is Lights Out

It seems to use a different (more powerful) sleep command because it will sleep the computer after a specified interval, even if it is doing something.

However, you can set sleep times individually for different programs if you want to let things run. So I have general sleep on 30 mins but a number of progs which I sometimes leave running doing batches or backups, I have set for a longer period or never.

A bit of work to set it up for my different progs but it really does sleep the machine.

Message was edited by: Mike Boreham

What does safari have to do with sleeping your mac?

Do you have a battery backup power system hooked up? Ever since I started using an APC BackUps device, I must manually put my iMac to sleep. Have not found a solution.

My Mac Pro is now sleeping!!!!

Turns out there was an update to Mozy (1.4) now the Mac goes to sleep as normal. It is strange because I did remove Mozy to see if it was the cause. Nonetheless I ma very happy my Mac Pro will go to sleep on its own!

Try updating your software to 10.5.8. Any luck?

What programs are running when you try to put it into sleep? Some programs prevent sleep while the program is running, or something is happening. Check the preferences of all those programs.

On the new 09 systems, bring it into Apple is probably the best way to permanently fix the issue.

One side note: In Windows, I notice that my computer freezes on the "preparing to enter sleep mode" window. I've associated this with certain programs that I've just quit. It seems that the programs might write some stuff into RAM or some cache that messes up the sleep process. If I do some other things, like opening and closing Explorer, an internet browser, and other Microsoft programs for a couple of minutes, sleep mode seems to work fine. Try doing the same—open and close some Apple programs right before you go to sleep.

i came here to start a thread that my computer won't sleep. I found dozens of them ahead of me. I have a new Mac Pro '09 with connected external eSATA drives and FW 800 partitions that contain files linked to programs on the main drive. I had lots of reasons to be suspicious and no ideas where to begin.

But just now I shut down the computer and shut down all drives. I started up the computer and did nothing. I had set the sleep interval to 5 minutes. It did not sleep. The most that happens is the screen goes dark. Sometimes when I make a manual sleep command it starts right up again.

There are so many posts like this. Should I just not worry about it and let the thing run all day and shut it off at night?

Could it be an eSATA card even if the drives connected to it are shut off? I have USB scanner and printer but they are shut off too.

My 2009 Mac Pro will not sleep either. Even installing Snow Leopard didn't help!

Pretty serious problem in my opinion. Is Apple going to reimburse us for all the wasted power?

I must relate my experience here.

I'm on this thread and a few others moaning like everyone how my computer would not sleep. On one of them there is a hint that led me to a conclusion. It said to look in the system.log for a clue. That's in the Console which I got to using the Go menu of Finder choosing /var/log.

When I got there I saw a cascading sequence of error messages still in progress. Three lines were repeating endlessly as a file could not be found and words I didn't understand said something was going to exit and try again in 10 seconds.

I called Apple Care immediately. And the fellow was so stumped he put me to tier 2 almost immediately. That woman was also stumped but told me to hold as there was someone who, if he was there, would know. I was in luck. He was there. And between me on the phone with her, and her messaging him, and her seeing my pasted error messages in the Mac Pro area of discussions where I had just posted them, he knew what to do!

He (through her) had me go to a file in my User Library which was the plist for the file that could not be found (over and over again) and remove it. I did. I restarted. The computer sleeps now!!

I don't know if those errors were repeating for months because I never looked in system.log before. But the non sleep issue for me had been a problem for that long, even across to a new computer using Migration Assistant and then to a new operating system. One hidden file into the trash later my computer sleeps like a baby.

It would be nice to know what error messages you got and what file you deleted. I also have this issue that my computer refuses got to sleep. The error messages in System Messages that is reoccuring every 15 min is:

"PubSubAgent[388] ==== SyncManager: Error sending messages to .mac: Error Domain=PSMessage Code=405 UserInfo=0x1bd310 "metod tillåts ej".

I have tried to delete "com.apple.PubSubAgent.plist", "com.apple.PowerManagement.plist". "com.apple.AutoWake.plist", but it doesn't help. Perhaps your actions can prove helpful for me.

okay. having same issue. I actually had a bunch of repeating messages in system.log about a program that i guess did not uninstall correctly so it kept searching for the file. fixed that and still no sleep. here is the diagnostic message if it means anything to anyone

11/13/09 7:14:08 PM configd[13]
Sleep: Early Failure - AC
com.apple.message.domain: com.apple.powermanagement.sleep
com.apple.message.signature: Early Failure
com.apple.message.result: Failure
com.apple.message.uuid: Unknown UUID