To delete an MQ writer

Start ESMAC for the enterprise server instance that is running the writer you want to delete.
On the ESMAC sidebar under Resources, select MQ from the drop-down menu.
Click Writers.
Click the Details button that corresponds to the writer you want to delete.
Click Stop to stop the writer.
Stopping the writer deletes it automatically.

Note: You can also delete writers using the casout command.