Your mail

Your Company Email — No Per-User Licensing

“Your mail” is a ready-to-use virtual machine image based on the open-source mailcow platform. You get email accounts on your own domain, a web interface, calendars, contacts, ActiveSync, antispam, and antivirus protection without having to manually assemble and configure a mail stack. Outgoing email is sent through Cloud Postbox using warmed-up IP addresses, so you do not need to build sender reputation from scratch, as you would when sending directly from a newly created virtual machine.

The number of mailboxes is not licensed separately. You pay for virtual machine resources, disks, the product according to Marketplace pricing terms, and outgoing email sent through Cloud Postbox. As the number of users grows, you may need to increase compute resources, storage capacity, and Postbox quotas.

Features

• email domains, mailboxes, aliases, quotas, and access policies;
• SOGo web interface for email, calendars, and contacts;
• IMAP, POP3, SMTP Submission, and ActiveSync for desktop and mobile devices;
• Rspamd antispam filtering and ClamAV antivirus scanning;
• DKIM, SPF, DMARC, TLS, and two-factor authentication;
• centralized administration through the mailcow web interface;
• migration of existing email using built-in IMAP synchronization jobs.

Who It Is For

• companies that need email on their own domain without per-mailbox licensing;
• teams that require control over their data, access permissions, and infrastructure;
• organizations that need shared calendars, contacts, and mobile synchronization;
• projects that are prepared to manage the VM, DNS, backups, and updates themselves.

Mailboxes and attachments are stored on the disk of your virtual machine in Yandex Cloud, which helps simplify compliance with the requirements of Russian Federal Law No. 152-FZ regarding the storage and processing of personal data.

How Outgoing Email Is Verified

Mailcow forwards outgoing email to Cloud Postbox, so the recipient verifies the IP address of the sending Postbox server against the domain’s single SPF record containing include:spf.postbox.yandexcloud.net and verifies the Postbox DKIM signature using its CNAME records. Postbox adds a DKIM signature aligned with the sender’s domain; therefore, DMARC passes based on DKIM and/or SPF, while an additional mailcow DKIM signature using a different selector does not conflict with it.

Cloud Postbox Pricing and Limits

The first 2,000 outgoing emails per calendar month are free of charge. After that, pricing depends on the monthly sending volume; current prices are available in the Cloud Postbox pricing documentation.

Initial Cloud Postbox quotas are 200 emails per 24 hours, 1 email per second, up to 200 recipients, and up to 10 MB per email. Quotas can be increased through Cloud Quota Manager or Yandex Cloud support. Detailed and up-to-date values are available in the Quotas and limits section.

1. Prepare Cloud Postbox

1. Create an address in Cloud Postbox for your primary email domain, for example
   example.com. Add the two Postbox DKIM CNAME records shown there at your DNS
   provider and wait until the status changes to Success. See the
   Cloud Postbox instructions.

2. Create a service account with the postbox.sender role. If the
   public DNS zone for the domain is hosted in Yandex Cloud, assign the same
   service account the dns.auditor and dns.editor roles.

2. Prepare the Network and VM

3. Reserve a static public IPv4 address in the availability zone where the VM will be created.

4. Create a security group or make sure that the security group assigned to the VM allows the required inbound TCP traffic.

   Port	Purpose
   25	receiving email from external mail servers
   80	HTTP-01 validation, Let’s Encrypt certificate issuance, and redirect to HTTPS
   443	mailcow web interface, SOGo, ActiveSync, and autodiscover
   465, 587	secure email submission from mail clients
   993	IMAP over TLS
   995	POP3 over TLS, if POP3 is used

   For administration, allow TCP port 22 only from trusted addresses.
   If necessary, also allow client ports 143 (IMAP with STARTTLS), 110 (POP3 with STARTTLS), and 4190 (ManageSieve).
   Outbound traffic must allow at least DNS, HTTPS, and TCP 587 to Cloud Postbox; the simplest option is to allow all outbound traffic.

5. In Marketplace, select the “Your mail” product and create a VM using the
   prepared static IP address and security group. In the Access section, specify
   the VM administrator and a public SSH key.

3. Provide First-Run Parameters

6. In Advanced → Service account, attach the prepared
   service account.

7. In the Metadata section, add:

   Key	Required	Value
   mailcow_hostname	required	Fully qualified server name, for example mail.example.com
   mailcow_admin_password	required	Your own mailcow administrator password, from 6 to 128 characters long
   mail_domain_base	if needed	Base domain if it cannot be derived from the server name by removing the first label

4. Publish DNS Records and Complete the Setup

8. If the zone is hosted in Yandex Cloud and the service account has the
   dns.auditor and dns.editor roles, the image will create any missing A, MX, SPF, DMARC, and
   mailcow DKIM records. Existing records are not overwritten.

   If DNS is managed by a third-party provider, the VM can be started before the A record is published. After the setup is complete, connect to the VM and retrieve the generated list:

   sudo cat /root/mailcow-dns-records.txt

If the A record was not present during the first check, acme-mailcow will retry the check in approximately one hour. To avoid waiting, restart the container after the A record becomes available:

   cd /opt/mailcow-dockerized
   sudo docker compose restart acme-mailcow

9. After the certificate has been issued, open https://mail.example.com and sign in with
   the username admin and the password specified in mailcow_admin_password. After a successful login,
   remove the mailcow_admin_password key from the VM metadata.

“Your mail” is already helping:

• small and medium-sized businesses — move to corporate email without relying on public email services;
• development teams — manage work correspondence and shared calendars in a secure environment;
• corporate departments — build a unified email infrastructure on their own domain;
• employees — securely access email, calendars, and contacts from any device.

For technical support, please contact support_mail@kodep.ru. We provide assistance with issues related to the image itself and mailcow; configuration of third-party DNS, email clients, and domains remains the customer’s responsibility.