How do I set up DKIM with A2 Hosting and troubleshoot validation issues?
Michael Ko
Co-founder & CEO, Suped
Published 20 Apr 2025
Updated 17 Aug 2025
7 min read
Setting up DomainKeys Identified Mail (DKIM) for your email domain is crucial for improving email deliverability and protecting your brand from spoofing and phishing attacks. It provides a way for recipient mail servers to verify that an email claiming to come from your domain was indeed authorized by the domain owner. This verification adds a layer of trust, helping your legitimate emails reach the inbox rather than being flagged as spam.
For users with A2 Hosting, configuring DKIM can sometimes present unique challenges, particularly when dealing with the specifics of their DNS management interface. The process might seem straightforward in theory, but subtle differences in how DNS records are entered or interpreted by various hosting providers can lead to validation issues. This is especially true when your domain registrar, DNS host, and email sending service are managed by different entities.
This guide will walk you through the steps to correctly set up DKIM records with A2 Hosting and provide practical troubleshooting tips for common validation errors. We will cover how to obtain your DKIM keys, add them to your A2 Hosting DNS, and verify that everything is configured properly, ensuring your emails are authenticated correctly and achieve better inbox placement.
Before you can add DKIM records to your A2 Hosting account, you need to generate them. These records are typically provided by your email service provider (ESP), such as iContact or Google Workspace. Your ESP will usually give you a hostname (also known as a selector) and a corresponding value (the public key).
Understanding DKIM selectors
A DKIM selector is a specific name that helps recipient mail servers locate the correct public key in your DNS. It's usually a short string, often like default or a unique identifier provided by your ESP, such as icontact123456. When you receive the DKIM record, it typically comes in the form of a TXT record with the hostname resembling selector._domainkey.yourdomain.com.
The public key itself will be a long string of characters. It is essential to copy this value precisely without any alterations. Any missing characters, extra spaces, or incorrect formatting can lead to validation failures, causing your emails to be marked as suspicious or rejected outright. Always double-check the key provided by your email service.
Adding DKIM records to A2 hosting DNS
A2 Hosting primarily uses cPanel for DNS management, which is a common interface for many web hosts. To add your DKIM records, you will navigate to the DNS Zone Editor within your cPanel. Look for either an "Advanced DNS Zone Editor" or simply "Zone Editor" option. Here, you'll select your domain and then add a new record.
Entering the TXT record correctly
When adding the DKIM TXT record, the hostname field requires careful attention. Some DNS interfaces, including A2 Hosting's, might automatically append your domain name to the hostname you enter. For example, if your ESP provides a hostname like default._domainkey, you should typically enter only default._domainkey into the hostname field, as the system will often append .yourdomain.com automatically.
A common mistake is entering the full hostname, such as default._domainkey.yourdomain.com, which could result in a duplicated domain, like default._domainkey.yourdomain.com.yourdomain.com. This incorrect entry will prevent DKIM from validating properly. Some interfaces also use a trailing dot (.) at the end of the domain name to signify an absolute path in DNS, but this is usually handled automatically and rarely needs manual input in hosting control panels.
Incorrect A2 hosting DNS entry
Entering the full domain in the hostname field leads to duplication and incorrect resolution. This is a very common pitfall.
After adding your DKIM records, the next crucial step is verification. DNS changes are not instant, and it can take some time for the updates to propagate across the internet. This delay, known as DNS propagation, is governed by the Time-to-Live (TTL) setting of your DNS records.
Waiting for DNS propagation
For most A2 Hosting DNS settings, the TTL for TXT records can range from 30 minutes to a few hours, often up to 4 hours or more in some cases. It's advisable to wait at least an hour before attempting to verify your records. Checking too soon might show outdated information, leading you to believe there's an issue when the record simply hasn't propagated yet.
Once sufficient time has passed, you can use online tools to check your DKIM record. These tools query DNS servers globally and report on the status of your DKIM setup. Simply enter your domain and the DKIM selector to get a validation report. If the setup is correct, the tool will indicate that the DKIM record is valid and configured properly. If it is not, then you will see an error. Learn more about how to verify DMARC, DKIM, and SPF setup.
Best practices for DKIM verification
Use multiple tools: Verify your DKIM record using several online DKIM verification tools to ensure consistent results.
Consult your ESP: Your email service provider will often have a built-in verification mechanism.
Send a test email: Send a test email to an inbox that allows you to inspect message headers (e.g., Gmail, Outlook). Look for a dkim=pass entry in the authentication results.
Troubleshooting common DKIM validation issues
Even with careful setup, DKIM validation issues can occur. These can range from minor typos to more complex DNS caching problems or discrepancies in how your email service provider interprets the records. Identifying the exact cause is key to resolving the issue efficiently.
Common issues and how to troubleshoot
One frequent problem, especially with hosting providers like A2 Hosting, is the automatic appending of your domain name, which creates a malformed record. Always ensure that the hostname entered into the DNS zone editor only contains the selector and ._domainkey, without your full domain.
If you're still facing issues, verify that your DNS is indeed managed by A2 Hosting. Sometimes, the domain's nameservers might point to a different provider, meaning changes made in A2 Hosting's cPanel won't take effect. Check your domain registrar (e.g., Name.com) to confirm the correct nameservers are set. Additionally, remember that DNS caching can cause delays. Even if your record is correct, it might take some time for all resolvers to pick up the changes. You may want to review how to troubleshoot DKIM failures more broadly.
Issue
Description
Solution
Hostname duplication
A2 Hosting (or cPanel) automatically appends your domain, resulting in selector._domainkey.domain.com.domain.com.
Enter only selector._domainkey in the hostname/name field.
Typographical errors
Any mistake in the public key or hostname.
Carefully compare the record entered with the one provided by your ESP. Copy-paste to avoid errors.
DNS propagation delay
Changes haven't updated across DNS servers yet.
Wait at least 1-4 hours, then recheck. The TTL (Time-to-Live) setting dictates the propagation time.
Incorrect nameservers
Your domain's nameservers are pointing to a different DNS host.
Update your nameservers at your domain registrar to point to A2 Hosting's nameservers.
Views from the trenches
Best practices
Ensure your DNS records are managed consistently, preferably all under A2 Hosting if they host your domain's DNS.
Always copy and paste DKIM keys directly from your ESP to avoid transcription errors and ensure accuracy.
Allow sufficient time for DNS propagation (typically a few hours) before troubleshooting.
Common pitfalls
Forgetting that A2 Hosting's cPanel might automatically append your domain to DNS records, causing duplication.
Not accounting for DNS propagation delays, leading to premature troubleshooting efforts.
Using incorrect DKIM selectors or having multiple, conflicting DKIM records for the same domain.
Expert tips
If DKIM validation fails, consider trying a different online DKIM checker to rule out tool-specific issues.
When dealing with split DNS management (domain registrar vs. hosting), ensure all parties are aligned on where DNS is hosted.
If your ESP is not validating, try sending a test email and examining the raw email headers for DKIM authentication status.
Marketer view
Marketer from Email Geeks says they were having trouble with DKIM setup on A2 Hosting for a domain bought from Name.com, with DNS and hosting on A2, and also set up in Google. The TXT record was not validating, though CNAME records were fine.
2023-11-09 - Email Geeks
Expert view
Expert from Email Geeks says that when troubleshooting DKIM on A2 Hosting, checking the public DNS records is very helpful. They recommended sharing the domain to allow for a direct lookup.
2023-11-09 - Email Geeks
Final thoughts on DKIM setup
Setting up DKIM with A2 Hosting requires attention to detail, especially concerning how hostnames are handled in their DNS zone editor. By understanding the common pitfalls, such as hostname duplication and DNS propagation delays, you can streamline the setup process and effectively troubleshoot any validation issues that arise.
Proper DKIM implementation is a foundational element of robust email deliverability. It assures recipient mail servers that your emails are legitimate, reducing the likelihood of them being marked as spam or rejected. This, in turn, boosts your sender reputation and ensures your messages reliably reach their intended audience.
By following the steps outlined in this guide and leveraging the troubleshooting insights, you can confidently configure DKIM for your domain hosted with A2 Hosting. A well-configured DKIM record is a significant step towards achieving excellent inbox placement and maintaining strong email communication.
Gmail, Outlook). Look for a dkim=pass entry in the authentication results.
A2 Hosting, is the automatic appending of your domain name, which creates a malformed record. Always ensure that the hostname entered into the DNS zone editor only contains the selector and ._domainkey, without your full domain.
