Your message to trstudent@headstart.co.uk couldn't be delivered.

trstudent wasn't found at headstart.co.uk.

webmaster Office 365 trstudent Action Required Recipient Unknown To address

How to Fix It The address may be misspelled or may not exist. Try one or more of the following: Send the message again following these steps: In Outlook, open this non-delivery report (NDR) and choose Send Again from the Report ribbon. In Outlook on the web, select this NDR, then select the link "To send this message again, click here." Then delete and retype the entire recipient address. If prompted with an Auto-Complete List suggestion don't select it. After typing the complete address, click Send. Contact the recipient (by phone, for example) to check that the address exists and is correct. The recipient may have set up email forwarding to an incorrect address. Ask them to check that any forwarding they've set up is working correctly. Clear the recipient Auto-Complete List in Outlook or Outlook on the web by following the steps in this article: Fix email delivery issues for error code 5.1.10 in Office 365, and then send the message again. Retype the entire recipient address before selecting Send. If the problem continues, forward this message to your email admin. If you're an email admin, refer to the More Info for Email Admins section below.

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More Info for Email Admins

Status code: 550 5.1.10 This error occurs because the sender sent a message to an email address hosted by Office 365 but the address is incorrect or doesn't exist at the destination domain. The error is reported by the recipient domain's email server, but most often it must be fixed by the person who sent the message. If the steps in the How to Fix It section above don't fix the problem, and you're the email admin for the recipient, try one or more of the following: The email address exists and is correct - Confirm that the recipient address exists, is correct, and is accepting messages. Synchronize your directories - If you have a hybrid environment and are using directory synchronization make sure the recipient's email address is synced correctly in both Office 365 and in your on-premises directory. Errant forwarding rule - Check for forwarding rules that aren't behaving as expected. Forwarding can be set up by an admin via mail flow rules or mailbox forwarding address settings, or by the recipient via the Inbox Rules feature. Recipient has a valid license - Make sure the recipient has an Office 365 license assigned to them. The recipient's email admin can use the Office 365 admin center to assign a license (Users > Active Users > select the recipient > Assigned License > Edit). Mail flow settings and MX records are not correct - Misconfigured mail flow or MX record settings can cause this error. Check your Office 365 mail flow settings to make sure your domain and any mail flow connectors are set up correctly. Also, work with your domain registrar to make sure the MX records for your domain are configured correctly. For more information and additional tips to fix this issue, see Fix email delivery issues for error code 5.1.10 in Office 365.

Original Message Details

Created Date: 2/10/2025 12:09:53 PM Sender Address: webmaster@inkscape.org Recipient Address: trstudent@headstart.co.uk Subject: Your registration on inkscape.org

Error Details

Error: 550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient trstudent@headstart.co.uk not found by SMTP address lookup Message rejected by: LOYP123MB3373.GBRP123.PROD.OUTLOOK.COM

Notification Details

Sent by: LOYP123MB3373.GBRP123.PROD.OUTLOOK.COM

Original Message Headers

Received: from CWXP123CA0003.GBRP123.PROD.OUTLOOK.COM (2603:10a6:401:73::15)
 by LOYP123MB3373.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:121::9) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8422.18; Mon, 10 Feb
 2025 12:09:59 +0000
Received: from CW2PEPF000056BD.GBRP265.PROD.OUTLOOK.COM
 (2603:10a6:401:73:cafe::2a) by CWXP123CA0003.outlook.office365.com
 (2603:10a6:401:73::15) with Microsoft SMTP Server (version=TLS1_3,
 cipher=TLS_AES_256_GCM_SHA384) id 15.20.8398.31 via Frontend Transport; Mon,
 10 Feb 2025 12:09:59 +0000
Authentication-Results: spf=pass (sender IP is 2605:bc80:3010::137)
 smtp.mailfrom=inkscape.org; dkim=none (message not signed)
 header.d=none;dmarc=bestguesspass action=none header.from=inkscape.org;
Received-SPF: Pass (protection.outlook.com: domain of inkscape.org designates
 2605:bc80:3010::137 as permitted sender) receiver=protection.outlook.com;
 client-ip=2605:bc80:3010::137; helo=smtp4.osuosl.org; pr=C
Received: from smtp4.osuosl.org (2605:bc80:3010::137) by
 CW2PEPF000056BD.mail.protection.outlook.com (2603:10a6:408:1::14) with
 Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id
 15.20.8445.10 via Frontend Transport; Mon, 10 Feb 2025 12:09:56 +0000
Received: from localhost (localhost [127.0.0.1])
	by smtp4.osuosl.org (Postfix) with ESMTP id AAEC7408D2
	for <trstudent@headstart.co.uk>; Mon, 10 Feb 2025 12:09:54 +0000 (UTC)
X-Virus-Scanned: amavis at osuosl.org
Received: from smtp4.osuosl.org ([127.0.0.1])
 by localhost (smtp4.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP
 id GMgzcoZsu3JU for <trstudent@headstart.co.uk>;
 Mon, 10 Feb 2025 12:09:53 +0000 (UTC)
X-Comment: SPF check N/A for local connections - client-ip=140.211.9.79; helo=inkscape1.osuosl.org; envelope-from=webmaster@inkscape.org; receiver=<UNKNOWN> 
DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org A1D82408C1
Received: from inkscape1.osuosl.org (inkscape1.osuosl.org [140.211.9.79])
	by smtp4.osuosl.org (Postfix) with ESMTP id A1D82408C1
	for <trstudent@headstart.co.uk>; Mon, 10 Feb 2025 12:09:53 +0000 (UTC)
Received: from inkscape1.osuosl.org (localhost [IPv6:::1])
	by inkscape1.osuosl.org (Postfix) with ESMTP id 74184F9BB
	for <trstudent@headstart.co.uk>; Mon, 10 Feb 2025 12:09:53 +0000 (UTC)
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: Your registration on inkscape.org
From: webmaster@inkscape.org
To: trstudent@headstart.co.uk
Date: Mon, 10 Feb 2025 12:09:53 -0000
Message-ID: <173918939345.27351.12977430505855403919@inkscape1.osuosl.org>
Return-Path: webmaster@inkscape.org
X-EOPAttributedMessage: 0
X-EOPTenantAttributedMessage: 1ddc0e1c-9ce0-4e21-8a1e-fba896eb37bd:0
X-MS-PublicTrafficType: Email
X-MS-TrafficTypeDiagnostic: CW2PEPF000056BD:EE_|LOYP123MB3373:EE_
X-MS-Office365-Filtering-Correlation-Id: 13195394-51ef-426d-bb4b-08dd49cbd60b