Turns the DDE server on or off.
/ddeserver [[on [service name]] | off]
You can also specify a service name for mIRC.
Note: mIRC's default service name is mIRC. The mIRC DDE Server defaults to on at startup unless it finds another mIRC or another application using it's current DDE Service name. If you have more than one mIRC acting as a DDE server then you should specify a different service name for each mIRC.