Why isn’t Vista sleeping?

Start your troubleshooting by running powercfg /energy from a command prompt.
When finished, copy C:\Windows\System32\energy-report.html to the desktop & open it with IE.

It said the print spooler was holding the computer from going to sleep. So I ran the printer troubleshooter which stomped on a few printer settings, rebooted the computer (which we had done before but it didn’t fix the issue and sure enough… it went to sleep automagically as it used to.

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