On 2007-02-22 17:57:31 -0500, "edisoned" jazzbookings@redacted.invalid said:
Hi, I've had this problem before where I can't put the Mac to sleep but it seemed to correct itself by running Disk Utilities but now that dosen't even help. I've got a G4 Tower running the latest OS. Any suggestions? Ed
USB devices or hubs often cause sleep problems. Will it sleep if you disconnect all USB devices, including keyboard and keyboard (use the power button for sleep). If you have ADC for the display, there is an USB hub in the display. The USB nub in my display caused sleep problems. You can test for this by unplugging the ADC and pushing the power button for sleep. You can tell if it works by the pulsing power light.
I had a Virus scanner for while on my PowerBook G4. The PowerBook would not sleep. I removed the Virus scanner and now the system works properly.
It was the free McAfee offer from Apple of a few years ago.
So, look through the processes running on the system as well as the previous post about external devices and you will find the culprit.