DOMAIN\user SQL Server login works with pyodbc/FreeTDS but fails with mssql_python

[Tage-Politi]

I am using mssql_python against an on-prem SQL Server using a domain-style username DOMAIN\username but with a password.

The same server, database, username and password work when using pyodbc with the FreeTDS ODBC driver, but fail with mssql_python. The error message is

mssql_python.exceptions.OperationalError: Driver Error: Invalid authorization specification; DDBC Error: [Microsoft][SQL Server]Login failed for user 'DOMAIN\username'.

To reproduce

This code below works:

import pyodbc
s=r"DRIVER=FreeTDS;SERVER=servername;PORT=1433;DATABASE=DM_Database;UID=DOMAIN\username;PWD=J...;TDS_Version=7.4;Encrypt=yes"
conn = pyodbc.connect(_s)

This code below fails with the message reported above:

import mysql_python
s = r"SERVER=servername,1433;Database=DM_Database;UID=DOMAIN\username;PWD=J...;Encrypt=yes;
conn = mssql_python.connect(s)

Further technical details

Python version: 3.10.12
mssql_python: 1.8.0
SQL Server version: SQL Server 2022 (Must be verified, but this is what my documentation says)
Operating system: Ubuntu 22.04.5 LTS

[github-actions]

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[Tage-Politi]

Database confirmeed to be:

Microsoft SQL Server 2022 (RTM-CU24-GDR) (KB5089900) - 16.0.4252.3 (X64) 
	Apr 26 2026 07:08:29 
	Copyright (C) 2022 Microsoft Corporation
	Developer Edition (64-bit) on Windows Server 2022 Datacenter 10.0 <X64> (Build 20348: ) (Hypervisor)