iMac won't go into sleep mode in Yosemite

Create a new User in System Preferences for testing.

Log out under the Apple in the Menu bar.

Log into new User. You can skip the Apple ID setup.

Does the Mac sleep correctly in the new User?

If no, then the problem is with your base files.

If yes, then the problem is in your User's folder.

I have the same issue in my macbook pro 13 inches.

I will be wondering if anyone knows how to fix this problem

MacBook Pro (13-inch, Early 2011)

What happens if you disable iCloud Drive?

Same problem, Macbook Pro Late 2013 won't go to sleep or turn on screensaver most of the time. Worked fine prior to upgrading to Yosemite.

I found a reason not mentioned in OS X Yosemite: If your Mac won’t go to or stay in sleep

If there are print jobs in the queue that cannot be printed because my printer is switched off, my iMac does not want to go to sleep either.

After printing the jobs, sleep works here again.

I've trawled the web looking for a cure for this and I came across a suggestion to unhook the ethernet cable and just connect by wifi. It's working for me. So far!

I've trawled the web looking for a cure for this and I came across a suggestion to unhook the ethernet cable and just connect by wifi. It's working for me. So far!

That actually works for me too. Thanks Tyke999... Of course, I hope to use ethernet connection in the future. But for now it works.

Have not had a chance to investigate this yet. As soon as I do I will let you know. Appreciate the help.

Spang1974

Creating a different/new user did nothing, same result. Not going to disable iCloud drive as I use it on a daily basis, and was one of the reasons I upgraded to Yosemite.

On a side note, I disconnected my network cable, and now the system goes to sleep, but can only be woken by the power button, and I cannot use ethernet anymore.

Cable is definitely NOT unplugged. Needed ethernet more than Sleep.

Spang1974

Unplugging the ethernet cable worked for a while but the wireless seemed to be messed up so I plugged it back in. It now seems to me that iTunes may be the problem. When iTunes is open the computer will not sleep. When I close iTunes the computer will sleep normally though it wakes up for a few seconds every couple of hours or so.

The sad part is that hunting "why does my Mac does not sleep" problems can only be done by trial and error. It would be more helpful if a log entry would be written somewhere why going to sleep was prevented. Now it is just guessing...

I found my cause/solution! In my Mac Preferences/Sharing I had Internet Sharing selected. It states when selected that computers connected via A/C power will not sleep while internet sharing is turned on.

For giggles I unselected it, and voila, no more sleep issues.

Not sure how or why I had it selected in the first place. Hope this helps someone.

Thanks for all the advice/responses!

GW

YES!! this solved it for me too.. Thanks man 🙂

workaround - System Preferences>>>Energy Saver>>>Computer Sleep - Never

- Never

uncheck all options.

Put Mac in Sleep Mode Manually.