How do I enable/disable command extensions?

A. A. When you use CMD.EXE, there are various extensions which are enabled by default. To enable/disable perform the following

1. Start the registry editor (regedit.exe)
2. Move to HKEY_CURRENT_USER\Software\Microsoft\Command Processor
3. Double click on EnableExtensions
4. Set to 1 for them to be enabled, or set to 0 for extensions to be disabled
5. Click OK

You can also enable/disable them for a specific command session by using the appropriate qualifier to cmd.exe

cmd /y disables command extensions for this cmd session
cmd /x enables command extensions for this cmd session