10-11-2026, 11:28 AM
Install the official Mail Server app in aaPanel Free Edition before adding your email domain or creating mailboxes. This lesson covers the installation task and service verification; DNS, certificates and delivery are separate lessons.
Test environment: Ubuntu 22.04.5, aaPanel Free Edition 8.0.6, 2 vCPU, 4 GB RAM and a 40 GB disk. The app offered Mail Server 7.4.1 on 11 October 2026.
1. Check the VPS before installation
Use a test server or take a recoverable backup first. Installing a mail server adds services and uses disk and memory; it is not just an extra button in the panel. Confirm that you have administrator access, free disk space and a domain whose DNS you control. Our lab had roughly 29 GB disk space available and 3 GB memory available before installation.
Check whether another mail server already occupies the SMTP/IMAP ports. Do not stop an existing production mail service merely to make a new installer work. Our initial listener check showed no existing SMTP or IMAP service.
Check outbound TCP port 25 with your provider. Our lab received an SMTP greeting from Google's receiving server, so that one outbound connection worked. This does not prove inbound port 25, recipient acceptance or inbox delivery. Providers can restrict port 25 independently of your local firewall.
2. Find the official Mail Server app
1. Sign in to the aaPanel installed on your VPS.
2. Select App Store in the left menu.
3. Enter Mail in the app search box and press Enter.
4. Find Mail Server with developer official and price Free.
5. Check the supported operating systems in that row. Our Ubuntu 22 server is listed.
6. Click Install on the Mail Server row.
The separate Anti-Spam Gateway search result is a different app. Do not install it instead of Mail Server.
3. Start the installation task
The installation window in our lab displayed Mail Server 7.4.1. Read the version, description and dependency warning before proceeding. If the plugin already exists, the installer warns that its files will be replaced.
![[Image: mail-install-branded-20261011.png]](https://adminsforum.com/uploads/tutorials/mail-install-branded-20261011.png)
Installation window: check the official app and version, then select Install Now.
Click Install Now once. aaPanel opens its Messages Box and adds Install[mail_sys-7.4.1] to the task queue. Open its execution log to follow progress. The app downloads software and installs dependencies, so this can take several minutes.
Do not click Install repeatedly. A Waiting install label or a successful task-queue message means the task was queued; neither is a completed installation. Compilation output also does not mean the queue is frozen.
4. Verify the installed services
Verified result, 11 October 2026: The installed plugin metadata reports Mail Server 7.4.1. Postfix, Dovecot and Rspamd report active. Redis responds but requires authentication. The lab website still responds successfully over HTTPS. No mailbox or external mail delivery is claimed at this stage.
After the task completes, return to the app list and open the Mail Server management screen. Record the actual service state. Check any initialization or missing-dependency messages rather than assuming all mail services are ready because the plugin appears installed. In our lab the new Mail dashboard requires an aaPanel vendor account before its configuration controls become available. The VPS panel login alone does not satisfy that separate account requirement.
5. Sign in to the separate aaPanel account
Open Mail Server from the left menu after the installation finishes. In our tested version, the management screen required an aaPanel.com account. This is different from the username/password used to enter your VPS panel. It is also different from the mailbox account you will create later.
If you already have an aaPanel.com account, use its email address and password in the vendor sign-in window. If you register a new account, use an email address that already receives messages. Do not use an address on the new mail domain before you have configured that domain and created its mailbox. Complete any verification requested by the vendor. Our lab used an existing working email and the account was bound successfully.
6. Initialize the mail-server environment
On the Mail dashboard, follow the environment Install or restore prompt if it appears. The Restoring the mail server environment dialog checks HostName, Postfix, Dovecot, Redis, Rspamd, SQLite support and SELinux. Read every row before pressing Submit.
Our lab initially failed HostName because it was only websrv. A mail hostname should be a full hostname, such as mail.example.com. Choose the name you will later use for the mail DNS A record. Our lab uses mail.adminslab.com. On our Ubuntu 22.04 lab, we set the static hostname over SSH:
Replace mail.example.com with your own hostname. This command changes the operating-system hostname; it does not create a DNS record or a PTR record. Existing servers may depend on their hostname, so check those dependencies before changing one.
![[Image: mail-environment-branded-20261011.png?v=1]](https://adminsforum.com/uploads/tutorials/mail-environment-branded-20261011.png?v=1)
Environment check: all nine rows are Ready before selecting Submit.
Return to the initialization dialog and click Refresh. All nine checks displayed Ready in our lab. Click Submit once and let the initialization log finish. aaPanel writes the mail-service configuration and starts the environment.
7. Confirm the installation outcome
After initialization, open Mail Domain. The Add Domain button should be available. An empty domain list is expected at this stage: you have installed the mail server, but have not added a mail domain yet.
For an additional service check on our Ubuntu lab, we used:
All three returned active. These are installation checks. An active service does not prove that Internet email will arrive or reach an inbox. Domain, DNS, TLS and delivery tests follow in separate lessons.
What installation does not complete
You still need a mail hostname, the domain's MX record, mailbox users, mail certificates and sender-authentication records. Reverse DNS is configured by the VPS provider. A website working over HTTPS does not prove email works.
Troubleshooting
Next lesson: Add adminslab.com to Mail Server and configure mail.adminslab.com. Do not send verification emails to [email protected] until the mailbox and receiving DNS are ready.
Test environment: Ubuntu 22.04.5, aaPanel Free Edition 8.0.6, 2 vCPU, 4 GB RAM and a 40 GB disk. The app offered Mail Server 7.4.1 on 11 October 2026.
1. Check the VPS before installation
Use a test server or take a recoverable backup first. Installing a mail server adds services and uses disk and memory; it is not just an extra button in the panel. Confirm that you have administrator access, free disk space and a domain whose DNS you control. Our lab had roughly 29 GB disk space available and 3 GB memory available before installation.
Check whether another mail server already occupies the SMTP/IMAP ports. Do not stop an existing production mail service merely to make a new installer work. Our initial listener check showed no existing SMTP or IMAP service.
Check outbound TCP port 25 with your provider. Our lab received an SMTP greeting from Google's receiving server, so that one outbound connection worked. This does not prove inbound port 25, recipient acceptance or inbox delivery. Providers can restrict port 25 independently of your local firewall.
2. Find the official Mail Server app
1. Sign in to the aaPanel installed on your VPS.
2. Select App Store in the left menu.
3. Enter Mail in the app search box and press Enter.
4. Find Mail Server with developer official and price Free.
5. Check the supported operating systems in that row. Our Ubuntu 22 server is listed.
6. Click Install on the Mail Server row.
The separate Anti-Spam Gateway search result is a different app. Do not install it instead of Mail Server.
3. Start the installation task
The installation window in our lab displayed Mail Server 7.4.1. Read the version, description and dependency warning before proceeding. If the plugin already exists, the installer warns that its files will be replaced.
Installation window: check the official app and version, then select Install Now.
Click Install Now once. aaPanel opens its Messages Box and adds Install[mail_sys-7.4.1] to the task queue. Open its execution log to follow progress. The app downloads software and installs dependencies, so this can take several minutes.
Do not click Install repeatedly. A Waiting install label or a successful task-queue message means the task was queued; neither is a completed installation. Compilation output also does not mean the queue is frozen.
4. Verify the installed services
Verified result, 11 October 2026: The installed plugin metadata reports Mail Server 7.4.1. Postfix, Dovecot and Rspamd report active. Redis responds but requires authentication. The lab website still responds successfully over HTTPS. No mailbox or external mail delivery is claimed at this stage.
After the task completes, return to the app list and open the Mail Server management screen. Record the actual service state. Check any initialization or missing-dependency messages rather than assuming all mail services are ready because the plugin appears installed. In our lab the new Mail dashboard requires an aaPanel vendor account before its configuration controls become available. The VPS panel login alone does not satisfy that separate account requirement.
5. Sign in to the separate aaPanel account
Open Mail Server from the left menu after the installation finishes. In our tested version, the management screen required an aaPanel.com account. This is different from the username/password used to enter your VPS panel. It is also different from the mailbox account you will create later.
If you already have an aaPanel.com account, use its email address and password in the vendor sign-in window. If you register a new account, use an email address that already receives messages. Do not use an address on the new mail domain before you have configured that domain and created its mailbox. Complete any verification requested by the vendor. Our lab used an existing working email and the account was bound successfully.
6. Initialize the mail-server environment
On the Mail dashboard, follow the environment Install or restore prompt if it appears. The Restoring the mail server environment dialog checks HostName, Postfix, Dovecot, Redis, Rspamd, SQLite support and SELinux. Read every row before pressing Submit.
Our lab initially failed HostName because it was only websrv. A mail hostname should be a full hostname, such as mail.example.com. Choose the name you will later use for the mail DNS A record. Our lab uses mail.adminslab.com. On our Ubuntu 22.04 lab, we set the static hostname over SSH:
Code:
sudo hostnamectl set-hostname --static mail.example.com
hostname -fEnvironment check: all nine rows are Ready before selecting Submit.
Return to the initialization dialog and click Refresh. All nine checks displayed Ready in our lab. Click Submit once and let the initialization log finish. aaPanel writes the mail-service configuration and starts the environment.
7. Confirm the installation outcome
After initialization, open Mail Domain. The Add Domain button should be available. An empty domain list is expected at this stage: you have installed the mail server, but have not added a mail domain yet.
For an additional service check on our Ubuntu lab, we used:
Code:
systemctl is-active postfix dovecot rspamdWhat installation does not complete
You still need a mail hostname, the domain's MX record, mailbox users, mail certificates and sender-authentication records. Reverse DNS is configured by the VPS provider. A website working over HTTPS does not prove email works.
Troubleshooting
- Still installing: Read the latest execution-log lines. If dependencies are downloading or compiling, let the active task finish.
- Download or package error: Record the exact failing URL/package and error. Check connectivity and disk space before retrying.
- Port conflict: Identify the service already listening. Preserve an existing mail deployment rather than removing it blindly.
- Mail features ask for an aaPanel account: This vendor account is separate from the VPS panel login and the email mailbox. Follow the actual account flow if required.
Next lesson: Add adminslab.com to Mail Server and configure mail.adminslab.com. Do not send verification emails to [email protected] until the mailbox and receiving DNS are ready.