How to get rid and replace the SERVER: Unknown command message?

[Haitam]

Hello, I am trying to learn PAWN scripting, how can I get rid of the SERVER: Unknown command message? And please tell me a good way to learn basics and start scripting! Thanks.

[Markski]

At the end of the OnPlayerCommandText callback, after your command code reaches the state where no command is found, send your own error normally with SendClientMessage, then return 1