Email sending failure

Email sending failure

Dear Zoho Support Team,

I hope this message finds you well. Apologies for the inconvenience, but I need your assistance with an ongoing issue.

Yesterday, I was unable to reply to one of my clients whose email is hosted by ProtonMail (proton.me). Upon investigation, I discovered that my domain had been blacklisted by Spamhaus. I promptly addressed this issue with them, provided proof that the listing was a mistake, and they have since removed my domain from their blacklist.

However, despite this resolution, I am still encountering the same bounce-back issue when attempting to respond to my client’s email. Below are the current SPF records for my domain: v=spf1 include:zoho.com ~all


Also here is the error reports
This message was created automatically by mail delivery software.
A message that you sent could not be delivered to one or more of its recipients. This is a permanent error.

xxxxxxxx@proton.me, ERROR CODE :554 - 5.2.1 Too many failures for the recipient



Reporting-MTA: dns; mx.zohomail.com
Arrival-Date: Sun, 13 Oct 2024 11:09:42 +0200

Original-Recipient: rfc822; xxxxxxx@proton.me
Final-Recipient: rfc822; xxxxxxx@proton.me
Status: 554
Action: failed
Last-Attempt-Date: 13 Oct 2024 09:09:47 GMT
Diagnostic-Code: 5.2.1 Too many failures for the recipient


Received:from mail.zoho.com by mx.zohomail.com
    with SMTP id 1728810582922135.48162122644794; Sun, 13 Oct 2024 02:09:42 -0700 (PDT)
Message-ID:<192852402e0.f6df3dbd28815.6915856235565997272@mydomain.org>
Date:Sun, 13 Oct 2024 11:09:42 +0200
From:Wise Bond Financials <xxxxxx@mydomain.org>
To:"Ascutney21" <xxxxxx@proton.me>
Subject:Re: Today is Day 7
Content-Type:multipart/alternative;
    boundary="----=_Part_87742_6127787.1728810582754"
User-Agent:Zoho Mail



      • Sticky Posts

      • Zoho Mail POP & IMAP Server Details

        Hello all! We have been receiving a number of requests regarding the errors while configuring or using Zoho Mail account in POP/ IMAP clients. The server details vary based on your account type and the Datacenter in which your account is setup. Ensure
      • Important update on Group Management | Zoho Mail

        Dear Zoho Mail Community, This post is to inform you all of the following updates on the Group Management in Zoho Mail. Group Member Addition: If a group member is added to an organization group in a Zoho Application, the member will be automatically
      • Mastering email etiquette and best practices to follow in Zoho Mail

        Hello Zoho Mail Community, We’re thrilled to invite you all to our upcoming webinar: Mastering email etiquette and best practices to follow in Zoho Mail. Join our live webinar for expert etiquette tips to enhance your professionalism and elevate your
      • 📣 📣 ZUG Meetups India - Explore Hybrid Workspaces using Zoho Workplace - Meet and Learn! 🧑🏽‍💻🧑🏽‍💻

        We are excited to announce the User Community initiative to meet you all in person and help you explore the need of the hour - Hybrid Workspaces using Zoho Workplace. We aim to help you to setup your Digital Workplace effectively so that your employees
      • Announcing Zoho Mail - Inactive user Policy

        Dear Zoho Mail users, Thanks to all of you for your continuous support.  We have recently started implementing the Inactive User Policy, for Zoho Mail.  A user is considered as inactive, if the user has not logged in to the Zoho mail account for a period of more than 120 days. The login through POP, IMAP and Active Sync are all taken into account for tracking the period of inactivity.  Whoever received the communication need not panic, as we have just communicated our policy to all the users.  To