insomniac mac

[Michael Grant]

I have an eMac running 10.4.9 that has refused to go to sleep for the
past week or so. AFAIK (it's mainly my wife who uses it), nothing new
has been installed or changed recently. If I choose Sleep from the
apple menu, it seems to spin down, the screen goes dark and the fan
goes off, but only for a split second before everything comes right up
again. I've logged in to different accounts to confirm that the
problem is not tied to any one account, but I really don't know where
else to start troubleshooting. Any ideas?

Thanks,
Michael

-- 
I never metadata I didn't like.