iMac won't awaken after sleeping

[mikora7]

Hi,
I am suddenly having the problem where my trusty mac crashes upon waking up from the screen saver or sleep mode. It is most often happening when my kids are playing games and they go away, come back and it won't wake up. What is does do is get as far as the white screen and doesn't progress any further. I found a few threads on this but the suggestions were to disconnect any iPods (none attached) and to disconnect the iPhone (again, none attached.)
I am running Os 10.6.8 on an iMac (which is about 6-7 years old) and have updated the browsers that I use. I am not sure if there are any tests I can run or where I should be looking for help in diagnosing this problem. Any suggestions?

 

[Detrius]

You're not running 10.6.8 on an iMac that's 6-7 years old. The first Intel iMac came out in January of 2006, so it's not possible that it's 6 years old (close, though).

Are there any error messages that come up after the machine is rebooted?

 

[mikora7]

Okay, then it's 5 years old. However, it is aging and it's definitely having troubles. Normally nothing comes up after a restart but sometimes we have to restart it twice to get it to start.
But this morning it started up with a folder with a question mark. The second time it started normally. Last night we repaired permissions but that should have made things better, not worse.

 

[Kaenon]

I just started having this same problem on my new 2011 iMac with the latest updates.

:s

 

[Detrius]

The blinking question mark points strongly to the hard drive. If you have any important data, make sure it's backed up.