nine.testrun.org is rejecting mails sent via deltachat from outlook.com

[timothyparez]

• Operating System (Linux/Mac/Windows/iOS/Android): Linux/Android
• Delta Chat Version: 1.46.2
• Expected behavior: Mails to be delivered normally
• Actual behavior: Rejected by nine.testrun.org
• Steps to reproduce the problem: Send message to any existing contact at nine.testrun.org from delta with outlook.com account
• Screenshots: n/a
• Logs:

nine.testrun.org rejected your message to the following email addresses:
<.... not disclosed on github ...>

Your message wasn't delivered because the destination email system rejected your message for security or policy reasons. For example, the email address might only accept messages from certain senders, or it might not accept certain types of messages, like those larger than a specific size.

Contact the recipient (by phone, for example) and work with them and their email admin to determine what policy or setting blocked your message and what you should do to make sure that future messages from you won't be rejected.

For more information, see [Status code 5.7.1](https://go.microsoft.com/fwlink/?LinkId=389365).

Generating server: TYCP286MB2098.JPNP286.PROD.OUTLOOK.COM

nine.testrun.org
Remote server returned '554 5.7.1 No valid DKIM signature found'

Original message headers:

ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none;
 b=BAbdcxjzQjAQyVXJKP8udWA+ixuaUPUMXmBuwoOoJtRgek9YQ2uMtvd2Hwrfv5ETxrTTlhgSLXh3+HCF5QWXROxJlaGzTLD3aki2T/JjbbfqBVz4WFlywCLkFEp9acrQN5LRRt9Hzz2akgS9pOBYu5yncwa6Jm4DZF9Nthi9v7ktCKlb6cJ+TmLV5taHhxf6bkdUtm3VSFxOwgP7klLV1SAz67jiv+D7ou2NmKhjEBX07ntCqswk7P6bl5XiXdc8Mlmb72swzRiuPrhoZDSru+8owbCykUvlnikHqH4pkOsYIpwMSCMZdspIcRNRSSzRfnU6IfpLY6cnhF5knWFxPA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com;
 s=arcselector9901;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1;
 bh=PPKOZFPEewfJjd02Q68Oga9SjMhCihr8K87uoQQSw/I=;
 b=dq49W/rIBoGs3jLe4ygrFGW6MqBiWMPdCR7ty60ioamh7qsPoN7kofH2PkOpJby20QWw85Q5qhWWWmCY02SBknL+4LLp9cUs6N3XQduj30MvqKr42tuO0+hUJOGwB7C1nrKpYJ03IEZ0UCLiym6xPMnWNN9zIGZFAQ9b43bVwwE9K6+S9X9i/W1Rq6sl/Dt3ueCIPbjJ8BLVrJBwmkfWKQAS3bBPMOEFSc/A+GpOZPaL4kcRQ9uaFxF8m1RljjvaEDVWYijqqfbomVXN65uePHldiCuf1i1imQhPsmkJCPVB5jL5uHXOtW0GO0aDpz5vTVb09hOnYz9AR5GA44ixiw==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=none; dmarc=none;
 dkim=none; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=outlook.com;
 s=selector1;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
 bh=PPKOZFPEewfJjd02Q68Oga9SjMhCihr8K87uoQQSw/I=;
 b=HS9LpOUDuMcfc8ly6jrWy7cbEdv0GCH27g/f+a+GWn5szvRJ7GosfqL/bqFRHeHCD+QAGUg/4iJjcRFNhYqgWMFu/m7qRQQD0JPlKzHmr0Ds8rn8iC/1cF9My689P+5u8ZsO2gc5rOHcG2AfNsU3HZ/O0KzSC4l8PLQKVAHlBFQ/+1uwbrmA4ik6+AcJSsif2PT1w7qaxIDxAX43rlHZSpjb/Q5ygpzNX0oux/3S1vp0Yu3Ljxkwc8isrzawL3F5rI+4WVv99uk5B+wK0NS5cSFQwgj1hzkWw4vpAXxXjIaxo0qNQgh3Kpy5TRPlb6vYlPvm5gdwPD1Lrl80tVGdBQ==
Received: from OS3P286MB1782.JPNP286.PROD.OUTLOOK.COM (2603:1096:604:170::9)
 by TYCP286MB2098.JPNP286.PROD.OUTLOOK.COM (2603:1096:400:151::5) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7719.33; Wed, 3 Jul
 2024 03:12:21 +0000
Received: from OS3P286MB1782.JPNP286.PROD.OUTLOOK.COM
 ([fe80::d1b8:96d5:447d:4c9f]) by OS3P286MB1782.JPNP286.PROD.OUTLOOK.COM
 ([fe80::d1b8:96d5:447d:4c9f%4]) with mapi id 15.20.7741.017; Wed, 3 Jul 2024
 03:12:21 +0000
Subject: ...

[link2xt]

According to dig TXT selector1._domainkey.outlook.com there is a DKIM key.

Does this happen with every email or only for some mails? Do you actually use outlook.com domain or a custom domain?

[timothyparez]

This started happening recently for EVERY contact @nine.testrun.org In group chats, the people using other domains than do receive my messages. It's a normal user@outlook.com address.

[link2xt]

There was a recent change https://github.com/deltachat/chatmail/pull/321 Maybe it is a problem. Original message headers do not use l=, but maybe there is a problem with length calculations.

[link2xt]

Change #321 is now reverted by https://github.com/deltachat/chatmail/commit/b1d11d7747c0d82bd78d3b632a734988ec33072c

@timothyparez could you check if the problem is fixed with this change?

[timothyparez]

Is the chatmail server at nine.testrun.org now running this patched version?

[link2xt]

Is the chatmail server at nine.testrun.org now running this patched version?

Yes, the latest commit on the main branch is deployed.

[timothyparez]

The issue seems to be resolved with this.