In later Windows versions, the Network DDE service may need to be enabled to receive calls.
[1] Windows Chat utilizes a split screen user interface similar to UNIX talk.
Windows Chat is real time text, with typing being transmitted immediately.
[2] Microsoft removed the application from Windows versions from Vista on, with the removal of NetDDE,[3] though the program and the DDE service it needs may be manually installed.
However the application can still be used through programs such as virtual machines if earlier versions of Windows are installed on them.