SMTP not working after updating to 1.17.2

Description

To Reproduce…

Steps to reproduce the behavior:

  1. Reply or new email.

  2. Send to any email.

Expected Behavior

Can send email on smtp (send.one.com).

Screenshots

Setup

1.17.2 (It works again, when i installed 1.17.0 again).

  • OS and Version: Windows 11 Pro - 24H2
    • Installation Method: mailspring.exe
  • Mailspring Version: 1.17.2

Additional Context

I got this error in the log :

----------SMTP----------

220 mailrelay6.pub.mailoutpod2-cph3.one.com ESMTP

OpenSSL version: OpenSSL 3.6.0 1 Oct 2025

init

EHLO Q58-Pro

250-mailrelay6.pub.mailoutpod2-cph3.one.com

250-PIPELINING

250-CHUNKING

250-SIZE 104857600

250-AUTH LOGIN PLAIN

250-ENHANCEDSTATUSCODES

250 8BITMIME

SASL_PATH:

SMTP Last Response Code: 250

SMTP Last Response: mailrelay6.pub.mailoutpod2-cph3.one.com

PIPELINING

CHUNKING

SIZE 104857600

AUTH LOGIN PLAIN

ENHANCEDSTATUSCODES

8BITMIME

mailsmtp Last Error Code: 296

mailsmtp Last Error Explanation: Unknown

mailsmtp Last Error Location: 10

mailsmtp Last Auth Type: 2

1.17.3 appears to fix the issue.