# Table of contents:

• Introduction
• Client/Request
• Server/Response
• Examples
  • Setting to AL (Allow messages by default)
  • Setting to BL (Block messages by default)
  • Already in that mode
  • Invalid argument
• Known changes

# Introduction

BLP is a command introduced with MSNP2.

It is a Notification Server command, without either a request or response payload.

It modifies if messages sent to you by users not on your Allow List (AL) are allowed to be received.

# Client/Request

BLP TrID [ AL | BL ]

# Server/Response

BLP TrID {list-version} [ AL | BL ]

Where list-version is the new List Version. Removed since MSNP10 in ABCHMigrated: 1 mode.

# Examples

# Setting to AL (Allow messages by default)

C: BLP 1 AL
S: BLP 1 256 AL

# Setting to BL (Block messages by default)

C: BLP 2 BL
S: BLP 2 257 BL

# Already in that mode

C: BLP 3 AL
S: BLP 3 258 AL
C: BLP 4 AL
S: 218 4

# Invalid argument

NOTE: This is an assumption. The actual error code here is unknown. It may also lead to an Instant Disconnection.

C: BLP 5 CL
S: 201 5

# Known changes

• MSNP10 and higher: List Versions are dropped in ABCHMigrated: 1 mode.