One of the reasons why people choose to clean their PC is because they want to stop PowerOff errors. The problem with PowerOff being a Microsoft-only command is that it won't work on most Windows computers and won't even work if Windows is completely shut down! This means that you will have to take the computer to your computer store (your local computer repair store or the internet) and get a new one, or get a PC copy from a site that will allow you to use the most up-to-date drivers on your computer. In many cases, people who buy computers with Windows as the operating system will have no option but to get a new one as the company might decide to support Windows 8 in the future.
One way to work around PowerOff is to edit your desktop. You can right-click the PowerOff icon which are in the task pane, select properties, and then click the Properties option. There you will see the following (assuming you're using Windows):
The PowerOff keystroke can be edited so that it restarts the computer. This can be done by right-clicking the PowerOff icon, selecting the option "Defaults," which will open a new dialog box where you can enter a new password for the PowerOff command so that the computer won't start automatically when Windows boots up. Alternatively, you can use the Linux command line "uci_restart" to instruct the system to restart (you'll need to know how to do this if you aren't familiar with Linux). The important thing is that the PowerOff keystroke instructs the system to halt all nonessential processor functions (this includes programs like Solitaire, Internet Explorer, and other low-level Windows programs that shouldn't be running while you're trying to fix the Windows PC).