Usage: UMODE e
Usage: MODE <nick> +|-e

e - Block DCC requests:
When this mode is set dcc transfers cannot be sent to your client. This is a good idea for children and computer novices. It is also useful for experts who do not want to be bothered by DCC requests. Since many files can be harmful, it is a good idea to leave this on and only turn it off if you have chosen to receive a file from someone you trust. You will still need to accept the file transfer. Do not run any scripts or files that you do not understand. Even harmless looking files might contain a virus. Avoiding all file transfers is the safest course.

Privilege: User

/mode Dan +e
/umode +e