Turn to this vital tool when programs or Windows goes wrong
Before graphical operating systems such as Windows caught on, most PCs ran DOS (short for Disk Operating System), which is a text-based system where you could move files and start programs by typing commands.
In fact, Windows effectively ran on top of this older operating system up to and including Windows 98 and Me. Modern versions of Windows can still create a DOS-like interface using the Command Prompt.
The command prompt isn’t so useful in everyday computing, but when programs or Windows go wrong it can be a vital tool. On its own it can be used to give additional instructions to many Windows programs, telling them to behave in a certain way when they start up.
Even more importantly, it’s the only way to run some of Windows’ most useful expert tools. In Windows XP, start the Command Prompt by clicking the Start button, clicking Run, then typing cmd in the box that appears and clicking OK.
Starting a Command Prompt is even easier in Windows 7 and Vista: simply click Start, type Command in the Start Menu’s search box and you should see ‘Command Prompt’ appear top of the results. Left-clicking this will start a regular command prompt, but to run most expert tools you’ll also need to make yourself an Administrator. To do this, right-click the ‘Command Prompt’ entry in the search results and choose ‘Run as administrator’. Answer Yes to the User Account Control dialogue box that appears.
The command prompt will appear as a black window into which you can type text, shown in white. For now, simply close the prompt by typing exit and hitting the Enter key. Alternatively, you can just close the Window, but we wouldn’t recommend it if you’re running one of the utilities described below.
Use Ping to troubleshoot your network Get information about your PC using the System Information
Clear your PC of clutter safely with Disk Cleanup
Revert to previous settings with System Restore





