Mac OS 9: PowerBook Doesn‘t Sleep With TCP/IP File Sharing Enabled

Under Mac OS 9, sometimes my PowerBook won't go to sleep after the time set in the Energy Saver control panel has elapsed. Why is this?
If the following conditions are present, your PowerBook may not go to sleep automatically:
You can put the PowerBook to sleep manually, however. The reason the PowerBook does not go to sleep automatically is because TCP/IP file sharing probes the computer name periodically, which can in turn reset the timer for automatic sleep.
Published Date: Feb 20, 2012