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Windows XP’s Run command provides a quick and easy way for experienced users to open files without the need to navigate through the Start menu or browse folders looking for a file. For example, if you type cmd.exe at the Run command and press Enter, a Command Prompt windows will open. Type msconfig.exe and the System Configuration Utility does the same.
You may also be aware of the fact that its not always necessary to enter certain file extensions when using the Run command. For example, entering just the filename portion of the command - say, cmd rather than cmd.exe - if OK because the EXE file extension is one of those tried by XP when an extension isn’t supplied. XP will attempt to use a number of file extensions when you don’t provide one, as dictated by it’s declared PATHEXT variables.
By default, the following PATHEXT system variables are declared by XP: .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH. One notable one that isn’t present is the .MSC extension used by saved MMC consoles. If you want pre-built consoles like the Services MMC to open without needing to type its full filename - services.msc - at the Run command, then you’ll need to add .MSC to the XP’s PATHEXT variable.
To add a new file extension to XP’s PATHEXT system variable, follow these steps:
1. Open the System applet in Control Panel.
2. Click the Advanced tab, and then click the Environment Variables button.
3. Double-click the PATHEXT variable in the System variables section and then click Edit.
4. After the .WSH entry, type a semi-colon and then type .MSC (no spaces required) and then click OK.
5. Reboot your system and then attempt to open the Services MMC from the Run command by simply typing services and then click OK.
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