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

                                  • Migrating a Zoho Forms form into Zoho Creator

                                    Hi, How can I migrate my Zoho Forms form into Zoho Creator? Thanks. Truly, Emad
                                  • Is there any way to recall an email sent using Zoho CRM?

                                    If an email is sent using Zoho Mail, there is a recall option/functionality that is available to the sender. Is there any way to recall an email if it was sent using Zoho CRM? I can't seem to find that option. Any help would be appreciated.
                                  • Quick Create needs Client Script support

                                    As per the title. We need client scripts to apply at a Quick Create level. We enforce logic on the form to ensure data quality, automate field values, etc. However, all this is lost when a user attempts a "Quick Create". It is disappointing because, from
                                  • is it possible to add more than one Whatsapp Phone Number to be integrated to Zoho CRM?

                                    so I have successfully added one Whatsapp number like this from this User Interface it seems I can't add a new Whatsapp Number. I need to add a new Whatsapp Number so I can control the lead assignment if a chat sent to Whatsapp Phone Number 1 then assign
                                  • Problem with reports due to "Connected" items change - Yes this IS a problem

                                    Now that the change has been made to use "connected" items I can no longer run the reporting I need in CRM. I should be able to start with Deals as the parent, connect down to the Account (Account_Name) on the deal as the child, then to any child items
                                  • Introducing notifications in the vendor portal

                                    Imagine this: You're a recruiter working with multiple vendors on a high-volume hiring project. You’ve just updated a job description after a last-minute change from the hiring manager. One of your vendors, however, is still working off the older version
                                  • CRM limit reached: only 2 subforms can be created

                                    we recently stumbled upon a limit of 2 subforms per module. while we found a workaround on this occasion, only 2 subforms can be quite limiting in an enterprise setting. @Ishwarya SG I've read about imminent increase of other components (e.
                                  • LESS_THAN_MIN_OCCURANCE - code 2945

                                    Hi I'm trying to post a customer record to creator API and getting this error message. So cryptic. Can someone please help? Thanks Varun
                                  • How to update "Lead Status" to more than 100 records

                                    Hello Zoho CRM, How do I update "Lead Status" to more than 100 records at once? To give you a background, these leads were uploaded or Imported at once but the lead status record was incorrectly chosen. So since there was a way to quickly add records in the system no matter how many they are, we are also wondering if there is a quicker way to update these records to the correct "Lead Status". I hope our concern makes sense and that there will be a fix for it. All the best, Jonathan
                                  • Analytics for notes created

                                    Is there a way I can see how many notes were created per day? Via reporting or analytics?
                                  • No TDS Deduction

                                    In some of our case, where we are reselling items at the same rate we purchased. In this scenario, Indian IT Law has a provision to request customer not to deduct TDS if the transaction value is same. TDS is paid by us (intermediary reseller) before we
                                  • Cannot update Recurring_Activity on Tasks – RRULE not accepted

                                    Hello, I am trying to update Tasks in Zoho CRM to make them recurring yearly, but I cannot find the correct recurrence pattern or way to update the Recurring_Activity field via API or Deluge. I have tried: Sending a string like "RRULE:FREQ=YEARLY;INTERVAL=1"
                                  • Add image to report...

                                    Greetings, I send a weekly color coded report via Creator email. I would like to add the legend somewhere in the report. Header, footer where ever. I have the legend saved on Google Drive and can access it via shared link. Sure someone has wanted to add
                                  • More controls for User Fields in CRM

                                    Dear All, We are here with a minor but crucial enhancement to the user fields—now set accessibility permissions to the records for user field. User field allows you to extend co-ownership of records to your peers. You can collaborate with them for certain
                                  • Calls to accounts rather than leads or contacts?

                                    So..... We have a dilemma and I'm hoping someone has encountered this before and figured out a fix. We have just migrated to Zoho. It's great.....expect for how "Calls" are handled.... We are B2B. We do not use the leads module. A "Lead/Prospect" for
                                  • Image Upload Field | Zoho Canvas

                                    I'm working on making a custom view for one of our team's modules. It's an image upload field (Placement Photo) that would allow our sales reps to upload a picture of the house their working on. However, I don't see that field as a opinion when building
                                  • Power of Automation :: Automated 'Delayed & Closed' Status Update Based on Due Date

                                    Hello Everyone, A custom function is a software code that can be used to automate a process and this allows you to automate a notification, call a webhook, or perform logic immediately after a workflow rule is triggered. This feature helps to automate
                                  • Lead Blueprint transition in custom list view

                                    Hi, Is It possible to insert the Blueprint transition label in a custom Canvas list view? I am using Lead module. I see the status, but it would be great if our users could execute the Blueprint right from the list view without having to enter the detailed
                                  • Range names in Zoho Sheet are BROKEN!

                                    Hi - you've pushed an update that has broken range names. A previously working spreadsheet now returns errors because the range names are not updating the values correctly. I've shared a video with the support desk to illustrate the problem. This spreadsheet
                                  • Has anyone integrated SMS well for Zoho Desk?

                                    Our company does property management and needs to be able to handle inbound sms messages which create a ticket for Zoho Desk. We then need to be able to reply back from Zoho desk which sends the user an sms message. This seems like a fairly common thing
                                  • populate email address and name in zoho desk?

                                    Is it possible to populate the email address and name in the zoho desk widget? We only use it in the context of an authenticated user, so we already know the user's name and email. Thanks,
                                  • Are there default/pre-built dashboards in Zoho Desk?

                                    Hi, I am looking for some pre-built dashboard templates in Zoho Desk, similar to what we can find in CRM/Projects, etc Thank you
                                  • SAP S/4 HANA to CRM Integration - change the SAP Client ID

                                    Hi I am trying to push the business partners from SAP S/4 HANA to ZOHO CRM module. The SAP Client ID is 421 in my case....kindly let me know how do I specify the sap client because it's a dropdown with specific values as of now. Thanks Ravi Aswani
                                  • Staff rules

                                    Hi! Do you people know what are the default staff rules when a new booking is created? We have two staff members in my team (me as the admin, and my employee). As we share the same services, I'm wondering how Zoho will pick the staff for new apointments.
                                  • Adding branded signature to tickets reply

                                    Hi, i am unable to figure out how to add signatures with logo to tickets reply. please advice .
                                  • Zoho Marketing Automation 2.0 - Landing Page function not working

                                    Dear Zoho Team, I am working on implementing Zoho Marketing Automation 2.0, and am now looking into the section "Lead Generation". If I open the "Landing Pages" section, I immediately get an Error code: Error: internal error occurred. Can you help me
                                  • Zoho Mail Android app update: Manage folders

                                    Hello everyone! In the latest version(v2.9) of the Zoho Mail Android app update, we have brought in support for an option to manage folders. You can now create, edit, and delete folders from within the mobile app. You can also manage folders for the POP
                                  • How to share ticket numbers across different ticket types

                                    I'm running an event and have three different ticket types. Add on Event + Main Event - Early bird Main Event only - Early bird Add on Event only - Early bird And Standard class - shown but not available until early bird finishes Add on Event + Main Event
                                  • Adding Social Media Buttons to Basic Campaigns

                                    Hi, I'm quote new to using Zoho Campaigns and I can't work out how to add Social Media Buttons into my basic campaign? In MailChimp there's a button that brings the icons into your campaign for you. I've tried adding the social media icons as 'buttons' in Zoho but it's not looking great. Can anyone help? Thanks!
                                  • Hide Inactive Social Sign-In Providers from Login Screen

                                    Hello Zoho Team, We hope you are doing well. Currently, Zoho One allows admins to configure security policies and enable or disable Social Sign-In options for third-party providers such as Apple, Google, Microsoft, LinkedIn, Yahoo, Twitter, Facebook,
                                  • [Free Webinar] AI Agents in Zoho Creator - Creator Tech Connect

                                    Hello Everyone! We welcome you all to the upcoming free webinar on the Creator Tech Connect Series. The Creator Tech Connect series is a free monthly webinar that runs for around 45 minutes. It comprises technical sessions in which we delve deep into
                                  • Download All Attached Files

                                    It would be extremely useful to have "download-all" functionality for downloading files attached to a task, subtask, comment, forum post or hosted in the "Documents" section etc. We've instructed our users to zip multiple files prior to uploading, but of course they forget all the time. Having to download lots of files one-at-a-time off a comment or task wastes a lot of time.
                                  • unable to send message reason 554 5.1.8 Email outgoing blocked

                                    unable to send message reason 554 5.1.8 Email outgoing blocked
                                  • Ship via Carrier Not Working Since Commerce Update

                                    Since the recent update to the Commerce platform, I can no longer use the ship via carrier function. It will take me to the address screen and let me verify them but when I go to save and move tot he next screen it will not do anything. This is happening
                                  • automations: Can I execute a step on a specific date?

                                    I have created a form in Zoho forms, and created a contacts list. I have also begun setting up an automation with the intention of sending the form to the contact list on a specific date every month (via email) for the entire year (essentially sending
                                  • Zoho Expense - The ability to add detail to a Trip during booking

                                    As an admin, I would like the ability to add more detail to the approved Trips. At present a requestor can add flights, accommodation details and suggest their preferences. It would be great if the exact details of the trip could be added either by the
                                  • Adding Folders in Android App

                                    Is it possible to create a new email folder within the Zoho Mail Android app?  Or can this only be done from the desktop version of Zoho Mail? Cheers!
                                  • Schedule Exports for Regular Project Updates

                                    Tracking project data often means exporting data at regular intervals. Instead of manually exporting data every time, users can schedule exports for Phases, Tasks, and Tasks in Zoho Projects. These exports can be set to run once, daily, weekly, or monthly
                                  • Question about custom fields using Pivot Tables.

                                    I have created a pivot table showing annual revenue of a client and how much payment that client is paying my company. Is there a way using pivot table to add an additional field that subtracts those to fields / shows me a percentage of that difference?
                                  • Request for Light/Dark Mode

                                    Would love the ability to switch between Light and Dark mode similar to Zoho CRM. https://help.zoho.com/portal/en/community/topic/introducing-dark-mode-light-mode-a-new-look-for-your-crm
                                  • Next Page