CITGTA, MTA & CIT FixCIT Tools

MTA:SA error code

MTA:SA error CD50

This MTA serial is already connected to that server.

How to fix it

  1. Close the other MTA

    Make sure no second MTA or GTA is still running, then wait a moment and connect again.

  2. Try the connection again

    Close MTA, open it again and connect once more. A single failed attempt can come from a restart on the server or a short break in your own connection.

Still not fixed? Copy the whole message, not only the code, and check your log in the Fix tool. It is read on your own computer.

About this code

It usually means a second MTA on the same computer, or a session that has not timed out yet.

A CD code appears when a connection to a server fails, is refused, or ends. Most of them carry a second line with the server's own reason. MTA's own documentation gives CD50 as Serial already connected.

Where this comes from

Read on 5 September 2026 and written in our own words here.