Q: iMac not sleeping when I press the power button (Mavericks)

I have the same issue on my new iMac after upgrading to 10.9. Power button seems to be disabled at the login screen. Pressing the button produces a beep and nothing happens.

I have the same problem. Sleeping only works if I am logged in. If I log out - pressing the power button only makes an alert beep. I have to click on sleep for sleeping.

Same here. I would like to have the tap function back.

there is catch from Apple, I use to press this button a lot on my iMac before leaving it on desk, but i noticed same as you, apple changed the way we use to put computer in sleep, now you have to press power button for two seconds then the shutdown menu will popup:

now froom here you have to select sleep option, Apple just killed the ease to putting your system on sleep.

I thought I was having the same problem, but I think I figured it out.

Apple must have changed the amount of time you have to push the power button to put the iMac to sleep. I can't just tap it any more, but if I hold for about a second then let go it will go to sleep. Hold for a little longer and the shutdown menu pops up.

Hope this helps

Thanks man, you are right, it works when i pressed it for 1 sec, but i keep it for more than 1 sec the other window poped up with other options as well.

The new feature of having both options of going to sleep or displaying the menu is quite neat... Just wish they would have told us with the update.

"But now I know... And knowing is half the battle!"

You wil have to go to the top left and click on the apple logo. And than you wil have to click on sleep. Hope this helped for you!