This is Version two as of October 2025. To set up Mailjet for sending authenticated emails from your domain, you’ll add and verify your domain in Mailjet, then create specific DNS TXT records in Cloudflare for domain validation, SPF, and DKIM authentication. After confirming these records in Mailjet, you’ll generate API credentials for SMTP access. Next, configure your email domain and mailbox in ISPConfig, ensure port 25 is open on your DigitalOcean VM, and finally connect everything using Thunderbird with the Mailjet credentials.
####################### mailjet
go to mailjet account https://app.mailjet.com/account
Add a domain or sender address https://app.mailjet.com/account/sender
click 'Add domain' button
Domain:example.com
Label:example
click add
We are going to select the DNS Record option. Write down:
Host: mailjet._460df0df
Value: 460df0dffd2381d24ea8e77f62d96da6
After accessing your DNS records for your domain, create a TXT record with the following value. For more details assistance in adding a TXT record
https://documentation.mailjet.com/hc/en-us/articles/360049641733-Authenticating-Domains-with-SPF-and-DKIM-A-Complete-Guide
Leave this page open
####################### CloudFlare
New Tab
2. login to your registar to add a DNS record, Example, CloudFlare
go to dns for theexample.com https://dash.cloudflare.com/d3df6cc4923a06a33b5a1869c7b2ccd2/example.com/dns/records
click add record
Type: txt
name: mailjet._460df0df
Content: 460df0dffd2381d24ea8e77f62d96da6
3. ####################### mailjet
Go back to mailjet tab
click validate
YOU WILL SEE:
account.sender.domain.validated.rocket
Your domain is now validated
You have successfully validatedexample.com. You can send using any email address ending in @example.com. Authenticate your domains now to improve your sender reputation and deliverability.
Click "Authenticate this domain (SPF/DKIM)
in the Setup cards, we will need this informatino to add a new DNS txt record in CloudFlare
You will have to do both
SPF
=====
Record Type: TXT
Hostname: @
Value: v=spf1 include:spf.mailjet.com ?all
DKIM
======
Type: txt
Hostname: mailjet._domainkey
Value: k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvh1r8nqXyeZQWWSRSK+6lDkkdd8/okq5d4zjl4BY/DkZjg2msoVtOjO5RQStAfSOUrSS0Fm0HvSft1NHp8uEZ6FBpoVoDcqBchluJDExat9yV/JVRQDGByXEOLrWO6tm1ywQmtXMaVD2qoQ8pi8tHqSO2m6PISu5RO9Dkr7Y2QK9BNwD3J8Hb3yjSk2ZxUcvXc8NErDTDgZSA6OlYMP6OKoFRC02KIJSpzVco1/o1APvByxxfjex1KPTLhtnCMiN7OkKWcXIt0g99UALbFq6IYWWcu2dfWA3oqS85i08fpLsH1IlN5Kc9l3kz1JMFBB6Z8S2UbVGUf6y8lk3UuKsLQIDAQAB
MX RECORD
==========
Type: MX
Name:example.com
Mail Server:example.com
TTL: Auto
Priority: 0
####################### CloudFlare
4. Go back to CloudFlare
click add two TXT records
SPF
=====
Type: txt
Name: @
Content: v=spf1 include:spf.mailjet.com ?all
DKIM
======
Type: txt
name: mailjet._domainkey
Content: "k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvh1r8nqXyeZQWWSRSK+6lDkkdd8/okq5d4zjl4BY/DkZjg2msoVtOjO5RQStAfSOUrSS0Fm0HvSft1NHp8uEZ6FBpoVoDcqBchluJDExat9yV/JVRQDGByXEOLrWO6tm1ywQmtXMaVD2qoQ8pi8tHqSO2m6PISu5RO9Dkr7Y2QK9BNwD3J8Hb3yjSk2ZxUcvXc8NErDTDgZSA6OlYMP6OKoFRC02KIJSpzVco1/o1APvByxxfjex1KPTLhtnCMiN7OkKWcXIt0g99UALbFq6IYWWcu2dfWA3oqS85i08fpLsH1IlN5Kc9l3kz1JMFBB6Z8S2UbVGUf6y8lk3UuKsLQIDAQAB"
NOTE: for some reason on the DKIM setup. i kept getting this error after I've added the DNS: There seems to be an error with your DomainKey record.
SOLVED: you will need wrap with double quotes
####################### mailjet
5. Go back to mailjet tab
Click on Refresh until the domain is validated.
you will see a message: Your SPF and DKIM record looks good!
# SETUP API IF NOT SETUP YET:
setup API you will need to setup and an API Credentials. Once you have created it, make sure to note the API key and the secret key. These will be your login and password for Thunderbird in the next steps.
go to account
go to SMTP and SEND API settings https://app.mailjet.com/account/relay
NOTE: I am only allowed one, i am going to try the existing forexample.com
####################### ISPCONFIG
go to the email tab
Domain > Add new domain if not listed
click on email mailbox
click on add new mailbox
Populate the fields and click save.
Name:example Support [Catchall]
Email @ Domain: [email protected]
Password: simple panel not noraml dash 25
Enable Receiving
####################### digital OCEAN (Hosting)
go to your hosting vm and open port 25 for TCP and UDP in the firewall
######### ############## THUNDERBIRD
File > New > mail Account
full name:example Support
email address: [email protected]
protocol: pop3
hostname: ISPCONFIG IP ADDRESS
port: 110
connection security: None
authentication method: normal password
username: [email protected]
Protocol: SMTP
hostname: in-v3.mailjet.com (https://app.mailjet.com/account/relay)
port: 465
connection security: SSL/TLS
Authentication Method: normal password
username: API Key (https://app.mailjet.com/account/relay)
Click Test
Clic Continue
Password:
[x] remember password