The standby and hibernate modes in Microsoft's Windows XP and the sleep mode in Vista are meant to be great time-savers. But too often a sleeping PC wakes up on its own--or doesn't awaken when you want it to.
The latter problem is particularly common with Vista, which is proving itself to be pretty worthless, even as Windows versions go.
The first time I set one of my XP systems to standby, it sprung to life each night, showing a message that my network was detected. The problem disappeared after I entered the machine's BIOS (press the key you're prompted to when your PC starts but before Windows loads), navigated to the Power screen, and set Wake on LAN to Disabled. (The location and wording of this setting varies from BIOS to BIOS.)
Another common source of untimely wake-ups is Windows' automatic updates. I prefer to update my OS manually because I don't like Microsoft or any other software vendor deciding when I should restart my PC. Of course, Windows isn't getting any safer or more reliable, so if you choose this option, be sure to get in the habit of checking for updates on your own about once a week.
To deactivate automatic updates in XP, click Start*Settings*Control Panel (or just Start*Control Panel, depending on your Start menu configuration), and double-click Automatic Updates. Select Turn off Automatic Updates, click OK, and close Control Panel.
In Vista, press the Windows key, type "Windows Update," click Change settings in the left pane, and choose Never check for updates (not recommended). You'll get a Security Alert icon in your system tray, but you can get rid of it by right-clicking the icon and choosing Exit. Unfortunately, XP doesn't give you the option to close this system-tray alert, so consider it a reminder to update Windows on your own.
You may also have to deactivate the auto-update settings of your antivirus and other programs and devices. Look for these settings in the apps themselves, or for hardware, check their Device Manager entries (see below for more on Device Manager fixes). Other sources of inadvertent wake-ups are backups and other operations you've created in Scheduled Tasks. To unschedule them in XP, double-click Scheduled Tasks in Control Panel, double-click each entry, choose the Settings tab, uncheck Wake the computer to run this task, and click OK.
In Vista, press the Windows key, type "Task Scheduler," and press Enter. Press Alt-C when prompted by User Account Control, navigate in the left pane to the task that's waking up your PC, select it in the middle window, and choose Disable in the right pane. Microsoft offers more information on disabling Vista's scheduled tasks in a knowledge-base article. Though it's specific to backup, the information applies to other tasks as well. Just be careful you don't disable a task that Vista needs to operate. You'll find descriptions of the Vista tasks you shouldn't disable on BlackViper.com.Then there are those times when your PC won't wake up when you want it to. Vista is particularly buggy in this regard, and unfortunately Microsoft hasn't done much to help Vista users find a solution. Sometimes the problem is associated with an out-of-date video driver. Visit your video-board vendor's site and look for a driver update. Another possible solution is a BIOS update, which you may be able to download from the site of whichever company made your system's BIOS. Other times the solution is as easy as enabling the wakeup feature of your mouse and keyboard. In XP, right-click My Computer, choose Manage, select Device Manager, navigate to and double-click the device's entry, choose the Power Management tab, check Allow this device to bring the computer out of standby, click OK, and exit Computer Management.
In Vista, press the Windows key, type "Device manager," press Enter, press Alt-C at the User Account Control prompt, navigate to and double-click the device's entry, choose the Power Management tab, check Allow this device to wake the computer, click OK, and close the Device Manager window.
You may also find a "Wake on keyboard" or similar setting in your BIOS settings, though I couldn't find such a setting in any of my XP or Vista systems. (I have three of the former and two of the latter for those of you keeping score at home.) The last bit of advice I have for people experiencing problems with standby or sleep is crude but effective, as Spock would say: Don't use these modes, at least until Microsoft decides the problems are important enough to fix, and instead shut off your system the old-fashioned way.
Tomorrow: A modest time-saving proposal: Dump your antivirus.