The procedure BeginTcpip, which informs the TCPIP address space that you want to start using its services, was unsuccessful.

errmsg is the text of the message that describes the error.

msgnum is the 4–digit numeric portion of the message identifier of the EZA message whose text is displayed in errmsg. For more information about this message, see message EZAmsgnum in the z/OS Communications Server: IP Messages Volume 1 (EZA).