iMac won't wake up from sleep using keyboard or mouse

After trying various solutions posted on this thread, I hit upon a little trick that is working for me. I set up one of my Spaces corners to manually put the monitor to sleep. Any time I walk away from the computer for an extended time, I simply run my finger down the track pad to invoke the manual display sleep. As long as I remember to do that, there are no problems waking. Otherwise, I've had the same problems as everyone else here. Can't really explain why it works, but it does. So far, anyway. Hat tip to Julian Velasco at Velapplog (his Apple blog) for this helpful suggestion.

texo55 wrote:
After trying various solutions posted on this thread, I hit upon a little trick that is working for me. I set up one of my Spaces corners to manually put the monitor to sleep. Any time I walk away from the computer for an extended time, I simply run my finger down the track pad to invoke the manual display sleep. As long as I remember to do that, there are no problems waking. Otherwise, I've had the same problems as everyone else here. Can't really explain why it works, but it does. So far, anyway. Hat tip to Julian Velasco at Velapplog (his Apple blog) for this helpful suggestion.

This may or may not work all the time. I tried doing this and it worked for a few days and then the problem happened again. I tried timing it too. I put the display to sleep manually and if I woke it up before 45 seconds it would be OK. Anytime after that it wouldn't wake up. I've rebooted and so far it's been OK (again).

I've given up entirely and now hoping for an updated to come through.

I am amazed at the wide spread nature of this problem but equally amazed that Apple hasn't picked up or commented on this. This certainly isn't of a severity requiring to send the Marines in, but of such a broad and impactful nature that it is damaging the Apple brand and quality reputation its OS and HW has earned. Why isn't Apple addressing this directly? I'm apparently one of the lucky few that was able to fix this (see my earlier post) but most here seem to have another root cause of their own issues. C'mon Apple!!

Just posting to say that I'm experiencing this problem with my August 2010 iMac i3 21.5. It started doing it all of a sudden a couple weeks ago. I don't have the computer go to sleep, but I do let the display sleep after 10 minutes. After I wake it up using the keyboard/mouse, the display will "sleep" (or shut off) at a random time during active use, and the keyboard/mouse won't wake it up. I've already had the logic board replaced twice, to no avail, and I've reset the SMC and PRAM with no success. There are no messages in the console that occur when this event happens. Seems like just not letting the display sleep is the only option to "fix" this.

I'm having the same problems with my 2010 iMac 28" i7 running 10.6.6 with bluetooth Apple mouse and keyboard.
It seems totally random phenomena, and it appears when least expected. I also only have the possibility of waking the iMac by shutting it down manually using the power switch on the back, then powering it up again.

Add me to the list, I have tried everything mentioned here and was told to reinstall the operating system by apple care with no joy. I'm very disappointed in this machine, I purchased it to get away from such problems. If you do a search on this issue it turns up hundreds of complaints and apple does not seem to admit it and the dealer is less than useless. Mine is 10.6.6 using the usb keyboard and wireless mouse.

Hello mekano, your solution has worked for me, so far. Its been a month since I had this problem. Thanks.

"Hello mekano, your solution has worked for me, so far. Its been a month since I had this problem. Thanks."

Care to share what solution that was? Desperate here.......

Update: Went 3-4 days without issue, then docked my iPad and my iMac froze after screen sleep. Had to force it to reboot. Reviewing the console logs revealed no issues with the iPad.

Hi Jason,

Is there nothing in the Console Messages or the system.log (in the Console messages) around the time of the incident?

Hello Warrior102
In the System Preferences, Desktop & Screen Saver, make sure the screen saver setting is timed to turn on before any of the Energy Saver settings. I.e. Screen Saver 15 min. "Computer sleep" and "Display sleep" >15min. mine is set to 20min.
However this might not be the solution. Time will tell; it's been a month since the last time I had the wake-up problem and I still expect it to happen.

I know this is a later post, but if anyone else is still having this problem or any success on finding a solution please respond. I am a bit skeptical of this machine at this point. A few months ago my hard drive crashed and it took a lot of my time to have it repaired, not to mention dealing with a couple of grumpy technicians who basically told me it wasn't Apple's fault but rather Western Digitals, the company who manufactures the hard drive. Mucho frustration, not looking forward to another round with these guys, but it's tough to turn my back on a $2100 machine. Also, the caps lock light on my keyboard intermittently works, not a huge deal, but for the price and name I was expecting a different animal from apple. Bummer.

From what I can tell it was just finishing up a time machine backup to time capsule, I forced reboot at 15:43:21.

Jan 23 14:08:53 iMac com.apple.backupd[12095]: Copied 1385 files (1.7 MB) from volume Macintosh HD.
Jan 23 14:08:53 iMac com.apple.backupd[12095]: No pre-backup thinning needed: 489.2 MB requested (including padding), 59.34 GB available
Jan 23 14:08:53 iMac com.apple.backupd[12095]: Waiting for index to be ready (100)
Jan 23 14:09:19 iMac com.apple.backupd[12095]: Copied 1041 files (43 bytes) from volume Macintosh HD.
Jan 23 14:09:30 iMac com.apple.backupd[12095]: Starting post-backup thinning
Jan 23 14:10:09 iMac com.apple.backupd[12095]: Deleted backup /Volumes/Time Machine Backups/Backups.backupdb/iMac/2011-01-22-134914: 59.34 GB now available
Jan 23 14:10:09 iMac com.apple.backupd[12095]: Post-back up thinning complete: 1 expired backups removed
Jan 23 14:10:09 iMac com.apple.backupd[12095]: Backup completed successfully.
Jan 23 14:10:13 iMac com.apple.backupd[12095]: Ejected Time Machine disk image.
Jan 23 14:10:14 iMac com.apple.backupd[12095]: Ejected Time Machine network volume.
Jan 23 14:10:23 iMac hdiejectd[12106]: quitCheck: calling exit(0)
Jan 23 14:23:11 iMac loginwindow[44]: loginwindow SleepWakeCallback WILL sleep
Jan 23 14:23:12 iMac kernel[0]: AFPSleepWakeHandler: going to sleep
Jan 23 14:23:13 iMac /System/Library/CoreServices/Finder.app/Contents/MacOS/Finder[184]: BonjourBrowser::DNSServiceQueryRecord returned -65540

Chalk another failing iMac to the heavily sedated category. I know this comment isn't useful but maybe if our collective screams are loud enough somebody from Cupertino will hear us.

Is these the messages from "Console messages" ? They do not look like mine.

I think there might be something useful in the Console Messages (at the top in my Console Message window - and in the "Diagnostic and Usage Messages" - could you check that - around the time when you tried to wake up the machine.