Screensaver stopped working

I noticed when I left my computer today and went away for half an hour when I got back the screensaver wasn't on.

So I changed the time from 15 minutes to 3, let it sit for 5 minutes, nothing.

Restarted and done the same and it appears to be working now.
Anyone know what could be the cause of this, perhaps a program i had open stopping the screensaver from coming on?

One of those annoying niggling bugs that I just need to find out why it happened so I can stop it from happening again.

If it happens a second time, then you probably need to try to figure out why, unless it's already next year.

Look to see what's running in the background possibly preventing the screensaver from activating. Open up your Activity Monitor.app and check.

chscag said:

Look to see what's running in the background possibly preventing the screensaver from activating. Open up your Activity Monitor.app and check.

Click to expand...

Well I know what's running anyway, but knowing what's running doesn't really provide me with any clue as to what's stopping the screensaver from coming on.

The computer screen doesn't 'sleep' either after 15 minutes.

It's happening again and I have no idea what's causing it.

'it just works'.

is this one of Apple's screensaver's or a Flash based? Have you tried selecting another ?

Yes, it's one of apples and i've tried others.

Oh and the computer won't sleep either, even if i set computer sleep to 1 minute then leave it, just never sleeps by itself.

Well I know what's running anyway, but knowing what's running doesn't really provide me with any clue as to what's stopping the screensaver from coming on.

The computer screen doesn't 'sleep' either after 15 minutes.

Click to expand...

The Activity Monitor.app not only shows what programs are running but also shows what processes are going on. There are processes that can prevent the machine from sleeping or a screensaver from activating.

You can also start trouble shooting by trying first to reset your SMC and PRAM/NVRAM. Don't be anxious to "toss off" a suggestion before you try it.

I love how people tend to blame Apple for problems when, in fact, they've already identified that it is their own error (program they left running) that is causing the issue. Yes, that's Apple's fault.

Andymac, you've already answered your own question: you're leaving a program open that won't let the mac go to sleep. The answer is "stop doing that."

If you've come to us from Windows, remember that closing a program's window does NOT automatically quit the program as it does on Windows. If you want the screen saver to run, you don't have to quit EVERY program, but you DO need to quit any program that interacts with the internet, or engages in any time of automatic activity (like auto-saving) -- otherwise, the computer will keep getting updated, and thus the screensaver and/or sleep never has a chance to come or (or stay on).

I'm in the habit of quitting every program as soon as I'm done with it, because even if I find I need it again it will take upwards of an entire SECOND for it to re-launch. This habit, which I picked up back in the olden days when RAM was an issue, has kept me completely free of screensaver- or sleep-related problems over the decades.

It's possible that something might have gotten corrupted. Try running repair permissions and or verify disks and see if that helps.. Check all your startup programs also as was mentioned programs that update themselves or even if you have uninstalled something.. Way back I was running a game in parallels and every time it seemed it would do it's timed update, the mac and parallels would freeze. I checked for running programs and crash logs and found that a demo of Drive genius I had installed and then uninstalled was still trying to load...

Good luck

@Aqua:

You do realize that you're responding to a thread that's well over a year old?

Oops LOL Now I do