Windows Shuts Down Your Computer When the Uninterruptible Power Supply Service is Started

You may experience either or both of the following behaviors:

• When you start the Uninterruptible Power Supply service, and you do not have a Uninterruptible Power Supply (UPS) attached to a COM port on your computer, the Uninterruptible Power Supply service starts, and then Windows XP shuts down.
• Your computer shuts down either before you log on or after you log on.

This behavior may occur if all the following conditions are true:

• The Power Fail/On Battery setting for UPS Signal Polarity is set to Negative in the UPS Configuration On: port dialog box.
• The UPS service is started.
• There is no UPS attached to the computer, or the UPS device is not working.

In Microsoft Windows 2000 and later, the operating system shuts down the computer if it detects that there is no power to the UPS.

To use the Uninterruptible Power Supply service, you must attach a working UPS device to your computer. If you do not have a working UPS device, start your computer in Safe Mode, and then use one of the following methods to work around this behavior until you can attach a working UPS device.

To start your computer in Safe Mode, remove all floppy disks and CDs, restart your computer, and then when you are prompted, or after the firmware POST process completes, press F8.

Method 1: Stop the UPS Service

1. Click Start, and then click Control Panel.
2. Click Administrative Tools, and then click Services.
3. Right-click the Uninterruptible Power Supply service, and then click Stop.

Method 2: Select "None" for UPS Device

1. Click Start, click Control Panel, and then click Power Options.
2. Click the UPS tab, click Select, and then click None.
3. Click Finish, and then click OK.

If you want to preconfigure many computers at the same time, but you do not want to connect a UPS while doing so, you can configure the Uninterruptible Power Supply service last. If you configure the Uninterruptible Power Supply service last, it is okay if you turn off your computer. You do not have to restart it. When the computer is put in service, you must attach the UPS to the COM port before you start the computer.