Making Email More Secure: Understanding DKIM and SPF

Making Email More Secure: Understanding DKIM and SPF

Imagine you’re sending an important letter to a friend. You write your message, put it in an envelope, and drop it in the mailbox with your address (From Address) and your friend's address (To Address). But what if someone along the way tampers with your letter, changes the contents, or even forges a letter pretending to be you? Your friend might receive a completely different message, or worse, never get it at all.



This is exactly the kind of problem businesses face with email security. Just like traditional letters, emails can be intercepted, modified, or forged. To protect email communication, organizations use two important security measures: DKIM (DomainKeys Identified Mail) and SPF (Sender Policy Framework).
Zylker Techfix encountered a major issue without these security measures : customers weren’t receiving support emails. Some emails bounced back, while others landed in spam folders. Without DKIM and SPF, email providers couldn’t verify whether Zylker’s emails were genuine or forged.

Understanding DKIM

Like official letters have signatures or company seals to prove authenticity, DKIM (DomainKeys Identified Mail) does the same for emails.

DKIM : The Signature Seal for Emails

  • DKIM attaches a cryptographic signature to every email you send.
  • When the recipient’s email service (like Gmail, Outlook, or Yahoo) gets the email, it checks this signature against your company’s domain records.
  • If the signature matches, the email is verified as authentic and delivered safely.
  • If the signature is missing or doesn’t match, the email might get rejected or marked as spam.

Adapting Custom SMTP for Public Domains

Using email forwarding and two-factor authentication, Zylker Techfix used public domains like Microsoft and Google with Zoho SMTP. Configuring DKIM was not the solution in this case; instead, the Custom SMTP setup within Zoho Desk resolved the issue. To further enhance security, they could enable Custom SMTP OAuth for a passwordless configuration.

Why did Zylker Techfix Implement DKIM?

Zylker Techfix used organization-level email addresses from a domain procured through their official website. These addresses were used by different departments. However, they faced email bounces due to authentication failures when sending messages via Zoho’s servers. This disrupted their customer support services, as bounced emails prevented ticket creation.
To resolve this, they enabled DKIM authentication in Zoho Desk. The setup was simple:
  1. Added the DKIM public key as a TXT record in their DNS settings.
  2. Verified the key using the "Verify" option in Zoho Desk.
  3. Ensured all outgoing emails carried the DKIM signature to authenticate email communications.
By enabling DKIM, Zylker Techfix significantly improved email deliverability, reduced email tampering, and prevented spoofing.

Understanding SPF

Now imagine you’re sending the package to your friend through a trusted courier service like FedEx or UPS. If someone tries to deliver a fake package using their branding, the courier service will refuse to accept it.
SPF (Sender Policy Framework) works in the same way—it ensures that only authorized mail servers can send emails on behalf of your domain.

SPF: The "Authorized Courier"

  • SPF acts as a list of trusted email servers that are allowed to send emails from your domain.
  • When an email is received, the recipient's email provider checks whether it came from an authorized server.
  • If the email comes from a trusted source, it is delivered; else it is rejected or marked as spam.

How did Zylker Techfix implement SPF?

Set up SPF by specifying specified email services as their authorized email senders.
To improve security, Zylker Techfix set up SPF records to tell email providers:
"Only emails sent from Authorized email servers should be considered legitimate. If an email comes from another server, don’t trust it!"

The Benefits
Setting up SPF prevented spam, fraudulent emails, and email spoofing while ensuring better email deliverability. 
After implementing DKIM and SPF, email deliverability improved, customers received emails without issues, and communication became more secure and professional.

Final Thoughts for Every Business
Whether you’re a small startup or a large enterprise, email security matters. Without DKIM and SPF, your business risks lost emails, email spoofing or tampered messages. 
Enable DKIM and SPF today!





      Zoho Campaigns Resources


        • Desk Community Learning Series


        • Digest


        • Functions


        • Meetups


        • Kbase


        • Resources


        • Glossary


        • Desk Marketplace


        • MVP Corner


        • Word of the Day


        • Ask the Experts


          • Sticky Posts

          • Register for Zoho Desk Beta Community

            With the start of the year, we have decided to take a small step in making the life of our customers a little easier. We now have easy access to all our upcoming features and a faster way to request for beta access. We open betas for some of our features
          • Share your Zoho Desk story with us!

            Tell us how you use Zoho Desk for your business and inspire others with your story. Be it a simple workflow rule that helps you navigate complex processes or a macro that saves your team a lot of time; share it here and help the community learn and grow with shared knowledge. 
          • Tip #1: Learn to pick the right channels

            Mail, live chat, telephony, social media, web forms—there are so many support channels out there. Trying to pick the right channels to offer your customers can get pretty confusing. Emails are most useful when the customer wants to put things on record. However, escalated or complicated issues should not be resolved over email because it's slow and impersonal.  When you need immediate responses, live chat is more suitable. It's also quick and convenient, so it's the go-to channel for small issues. 
          • Welcome to Zoho Desk Community - Say hello here!

            Hello everyone! Though we have been here for a while, it’s time to formally establish the Zoho Desk Community; we’re really happy to have you all here! This can be the place where you take a moment to introduce yourself to the rest of the community. We’d love to hear all about you, what you do, what company or industry you work for, how you use Zoho Desk and anything else that you will like to share! Here’s a little about me. I am Chinmayee. I have been associated with Zoho since 2014. I joined here
          • Webinar 1: Blueprint for Customer Service

            With the launch of a host of new features in Zoho Desk, we thought it’ll be great to have a few webinars to help our customers make the most of them. We’re starting off with our most talked about feature, Blueprint in Zoho Desk. You can register for the Blueprint webinar here: The webinar will be delivered by our in-house product experts. This is a good opportunity to ask questions to our experts and understand how Blueprint can help you automate your service processes. We look forward to seeing

          Zoho CRM Plus Resources

            Zoho Books Resources


              Zoho Subscriptions Resources

                Zoho Projects Resources


                  Zoho Sprints Resources


                    Zoho Orchestly Resources


                      Zoho Creator Resources


                        Zoho WorkDrive Resources



                          Zoho CRM Resources

                          • CRM Community Learning Series

                            CRM Community Learning Series


                          • Tips

                            Tips

                          • Functions

                            Functions

                          • Meetups

                            Meetups

                          • Kbase

                            Kbase

                          • Resources

                            Resources

                          • Digest

                            Digest

                          • CRM Marketplace

                            CRM Marketplace

                          • MVP Corner

                            MVP Corner




                            Zoho Writer Writer

                            Get Started. Write Away!

                            Writer is a powerful online word processor, designed for collaborative work.

                              Zoho CRM コンテンツ



                                ご検討中の方

                                  • Recent Topics

                                  • blank page after login

                                    blank page after logging into my email account Thanks you
                                  • WriterTh

                                    After every space Writer goes to capital letters mode in my Android tablet. The cap mode stays till the second letter is typed in the word then it comes to normal mode.
                                  • Does Thrive work with Zoho Billing (Subscriptions)?

                                    I would like to use Thrive with Zoho Billing Subscriptions but don't see a way to do so. Can someone point me in the right direction? Thank you
                                  • Zoho writer unable to merge documents to PDF with basic fonts in Hebrew or fonts from my computer

                                    I created several forms that will be merged into PDF files through Zoho Writer and I am unable to receive the PDF in the basic fonts of the Hebrew language or in the fonts I have on my computer. The writer exports to PDF an exchange font that looks very
                                  • I have already created some Bots, Commands, and Widgets in Cliq, but I am still not seeing the “Create Extension” option in my account. Could you please help me enable or access this option?

                                  • How to setup DKIM / SPF in Zoho Mail

                                    Hello there! I'm having a hard time understanding how to setup the TXT records for SPF and DKIM with Zoho Mail. I'm following the instructions here: https://www.zoho.com/campaigns/help/setup-spf-dkim.html Specifically, when it comes to the value for the
                                  • Cliq iOS can't see shared screen

                                    Hello, I had this morning a video call with a colleague. She is using Cliq Desktop MacOS and wanted to share her screen with me. I'm on iPad. I noticed, while she shared her screen, I could only see her video, but not the shared screen... Does Cliq iOS is able to display shared screen, or is it somewhere else to be found ? Regards
                                  • Infinite loop of account verification

                                    Hi I can't do anything on my zoho account.  I always get this message Hi Sheriffo Ceesay As a security measure, you need to link your phone number with this account and verify it to proceed further. When ever I supply the details, it displays that the number is associated with another account. I don't have any other account on zoho so this is really annoying. 
                                  • How we cut CRM updates from ~20 minutes down to 2, our real workflow

                                    Updating the Zoho CRM after every call used to be one of the biggest time sucks for our team. By the time you write your notes, clean them up, fill in the fields, and log everything properly… you’ve easily lost 15–20 minutes per call. We started experimenting
                                  • Arattai App Features Update

                                    1. Offline Messaging & Sync Enable users to compose messages without internet and deliver them automatically via peer-to-peer methods (Bluetooth/WiFi Direct) when nearby users are available. This would be a game-changer for rural India with unreliable
                                  • Zoho Books Sandbox environment

                                    Hello. Is there a free sandbox environment for the developers using Zoho Books API? I am working on the Zoho Books add-on and currently not ready to buy a premium service - maybe later when my add-on will start to bring money. Right now I just need a
                                  • How to add Product Add-Ons, Mandatory Forms, and Auto-Save Address in Zoho Commerce

                                    Hi all, I need help setting up several behaviors in Zoho Commerce. I can’t find the correct configuration options, so I want to confirm whether these are supported or if there is a workaround. 1. Product-Specific Add-Ons (Example: GWB Subscription) When
                                  • Zoho Workdrive - Communication / Chat Bar

                                    Hi Team, Please consider adding an option to allow admins to turn on or off the Zoho Communication Bar. Example of what I mean by Communication Bar: It's such a pain sometimes when I'm in WorkDrive and I want to share a link to a file with a colleague
                                  • Proposal for Creating a Unique "Address" Entity in Zoho FSM

                                    The "Address" entity is one of the most critical components for a service-oriented company. While homeowners may change and servicing companies may vary, the address itself remains constant. This constancy is essential for subsequent services, as it provides
                                  • Request for Auto PO - Min–Max based Automated Purchase Feature

                                    Dear Zoho POS Team, I’m writing to request a feature enhancement that would significantly streamline inventory management for businesses using Zoho POS — particularly supermarkets, FMCG retail, and multi-store operations like ours. Feature Requested:
                                  • Zohomail

                                    Im trying to setup email address zoho
                                  • PROBLEMA

                                    Salve, non riesco a inviare email, e mi esce una tabela errore temporaneo. come posso risolvere il problema ?
                                  • Forever FREE Business Email with Zoho Mail

                                    Forever FREE Business Email with Zoho Mail: is it available?
                                  • Weekly Tips : Make collaboration effortless with Whiteboard in Zoho Mail

                                    Working with your team often means switching between emails, notes, and other applications just to explain an idea. Maybe you are trying to sketch a layout, plan a workflow, or quickly brainstorm ideas—with text alone, things can get confusing. So how
                                  • Formula field number of days between 2 dates

                                    Hi, I want to have a formula field which calculates the following: IF EndDate < TODAY and Oproep is true (this is a checkbox field) than EndDate - StartDate, otherwise TODAY - StartDate It should calculate the number of days How can I write this for
                                  • Tracking Snippet not working in Zoho Marketing Automation!

                                    First off, the fact that you have to wait about 12-24 hours for every response is terrible. How are we supposed to conduct business? Second, we have been trying for several days to get the Tracking Code Snippet in marketing automation to work, to no avail.
                                  • 'email address already exists'

                                    I deleted a user from my organization and want to use the same email address that user had, but the email address seems to still exist somewhere as I get 'email address already exists' when I try and create it. I have deleted the entire organization and
                                  • ZOHO reporting DKIM entries are not configured, when they have been configured and verified by 3rd parties

                                    Why is ZOHO reporting to my organisation users the following: "The DKIM entries in your domain's DNS records are not configured. Please contact your administrator for configuring DKIM to ensure optimal RSVP invite delivery." When I have configured the
                                  • Manage Bookings directly from Zoho Mail

                                    Greetings from the Zoho Bookings team! We’re introducing the new Zoho Bookings extension for Zoho Mail, designed to help you view appointments, copy time slots and share booking links without leaving your inbox. This integration brings scheduling right
                                  • My notes from the past 2 months have disappeared

                                    Hola, necesito ayuda urgente. Hoy, al iniciar sesión en mi Zoho Notebook como todos los días, me llevé una gran sorpresa al descubrir que todas mis notas de los últimos dos meses habían desaparecido. Estas notas son muy importantes para mí, ya que uso
                                  • How can I load a network into the cliq desktop app?

                                    I have both the standard cliq log in for my org and I am part of a cliq network. In the browser I can choose which I log in to. However, in teh desktop app if I log in it will alwasy load my org's cliq. Can I switch this to the network I have create
                                  • Ability to modify what displays in calendar invite?

                                    I am a long time calendly user and want to make the switch to bookings.  I understand that there is not currently a meets/hangouts integration, is one on the roadmap? Is there anyway I can modify the calendar invite to include the meet link?  I can add it to the emails no problem, but I would also like it to display on their calendar.  Is there some work around I can do to get it on the calendar?  Also am I able to modify the calendar event title?
                                  • Issue with Booking Confirmation Page Not Displaying, Leading to Customer Anxiety and Unnecessary Support Calls

                                    I am writing to express my growing concern regarding the confirmation process in Zoho Bookings, particularly the inconsistent display of the confirmation page after a successful payment. As a mobile service provider, I rely on Zoho Bookings platform for
                                  • Is it possible to turn off all capabilities for a customer to schedule, reschedule or cancel an appointment?

                                    Is it possible to turn off all capabilities for a customer to schedule, reschedule or cancel an appointment? I would like to set it up so only staff can schedule appointments. Is this possible?
                                  • Is there a way to generate a virtual meeting for a group service in Zoho Bookings?

                                    Are virtual meetings not supported for group services/meetings? I have integrated Zoom with one-on-one services, but I need a way to create an online group meeting. Thanks
                                  • Introducing VeriFactu Support in Zoho Books

                                    Hello users, Spain has introduced the VeriFactu system under Real Decreto 1007/2023 to ensure integrity, traceability, and anti-fraud compliance in e-invoicing. Starting January 1, 2026, all B2B invoices must be reported to Agencia Estatal de Administración
                                  • Where we can change the icon in social preview

                                    Hi, we changed our logo, and the image that appear in preview (ex : when we post a appointment link somewhere) is still our old logo. I did change our logo in the org setting. https://bookings.zoho.com/app/#/home/dashboard/settings/basic-info?clview=false
                                  • Zoho Bookings changes Lead Source

                                    Hi. i would like to know if there's a way for Zoho Bookings to not change the lead source when booking a lead for an appointment as the lead source will be used in a report. Scenario: Lead source: Website after booking an appointment Lead source: Zoho Bookings Thanks. Dan
                                  • Need to set workflow or journey wait time (time delay) in minutes, not hours

                                    Minimum wait time for both Campaigns workflows and Marketing Automation journeys is one hour. I need one or the other to be set to several minutes (fraction of the hour). I tried to solve this by entering a fraction but the wait time data type is an integer
                                  • Suggestion: Associating Assets with Company in Zoho FSM

                                    Hello Team, I would like to share an idea based on practical experience. Currently, all assets in the Zoho FSM Asset module are linked to a specific contact person. I would like to know if it is possible to associate assets with a company instead. This
                                  • Zoho Inventory / Finance Suite - Extend Visibility of File Names on Attachment Fields

                                    Hi Inventory / Finance Suite team, I noticed recently that when you add an attachment field to a module in Inventory, only the first 8 characters of the file name are visible on the details view. 8 characters is not a useful amount and there is plenty
                                  • Many Notes Becoming Unusable

                                    Hello. The Notebook app is becoming unusable. I'm getting odd-looking results from my searches. Some of the notes, after clicking on them, show an update button that does absolutely nothing. Not sure what has happened, but it would be nice to get this
                                  • Kaizen #218: Actions APIs - Field Updates

                                    Hello all!! Welcome back to a fresh Kaizen week. In the previous weeks, we covered Workflow Rules APIs, Actions APIs - Email Notification APIs, and Tasks Update APIs. This week, we will continue with another Actions API - the Field Update API in Zoho
                                  • How Contract Types and Templates Form the Backbone of Zoho Contracts

                                    Every contract in Zoho Contracts starts with two essential elements: Contract Type and Template. These are not just administrative steps. They define how every contract in your organization is created, governed, and managed over time. Let us look at the
                                  • E-Invoicing in Belgium with Zoho Books

                                    Starting January 1, 2026, Belgium is introducing mandatory electronic invoices (e-invoicing) for all B2B transactions between VAT-registered businesses. This means that invoices and credits notes must be exchanged in a prescribed digital format. How E-Invoicing
                                  • Next Page