501: Syntax Error. Only ListId or Userid allowed as argument to this command

Severity

Recoverable error.

Explanation

An incorrect VRFY or EXPN command was entered. Enter a user ID or mailing list after the VRFY and EXPN commands.

System action

SMTP continues.

System programmer response

Correct the command syntax, and try again.

Module

SMTPCMDS

Destination

DoVrfyExpn

Parent topic: SMTP reply code messages