Knowledge base · Mailhosting
Mailhosting — guides
Set up mail hosting, migration, DKIM/SPF/DMARC, Sieve filters, shared calendars.
Overview
30 articles in this category
From setup to advanced topics, in a sensible order.
First login as domain admin in the Mailcow GUI
After ordering your mail server plan, you get access to the Mailcow GUI. Here's an overview of what you see as domain admin and where to find what.
Creating and editing mailboxes, setting quotas
How to create new mail addresses as domain admin, assign storage quotas, change passwords and delete mailboxes again.
Setting up aliases and a catchall
Route several mail addresses into one mailbox — info@, kontakt@, presse@ all in a single inbox. Plus a catchall for every typo address.
Creating app passwords for mail clients
With 2FA active, Outlook, Apple Mail and friends need an app password instead of your main password. How to create them, revoke them and avoid password chaos.
Setting domain-wide Sieve filters as domain admin
Filters that apply to all mailboxes of your domain at once — for example to sort newsletters domain-wide into a specific folder or to reject certain senders.
SOGo webmail — first login and overview
SOGo is the web interface for your Mailcow mailbox. Mail, calendar, contacts, tasks — all in the browser. Here's how to find your way around.
SOGo calendar — events, reminders and sharing
SOGo gives you more than mail: a full calendar with sharing, reminders and sync to iPhone, Android and Outlook.
SOGo contacts and address book
Using the address book in SOGo — create contacts, manage groups, sync with your smartphone and mail clients via CardDAV.
Personal Sieve filters in SOGo webmail
Sort mail into folders automatically, set up an auto-reply, adjust spam thresholds — all directly in webmail, without the domain admin lifting a finger.
Understanding spam and junk — whitelist, blacklist and quarantine
How Mailcow detects spam, what the spam score means, when a mail lands in quarantine, and how you clear legitimate senders.
Setting up Apple Mail (macOS) — profile import and the manual way
Two ways to connect Apple Mail on the Mac to your Mailcow mailbox: via a .mobileconfig profile or manually with IMAP/SMTP — plus CalDAV/CardDAV for calendar and contacts.
Setting up Apple Mail on iPhone and iPad
Connect the iOS Mail app to Mailcow — via a profile (.mobileconfig) or manually with IMAP/SMTP, plus CalDAV/CardDAV for calendar and contacts.
Setting up Outlook on Windows — all versions
Connecting Microsoft Outlook (2019, 2021, 365, new Outlook) on Windows to Mailcow — autodiscover, manual configuration, exporting and importing Outlook profiles.
Setting up Thunderbird — Windows, macOS, Linux
Thunderbird is the most popular open-source mail client. Cross-platform, free, connects directly to Mailcow. Here's the setup on all three operating systems.
Server details reference — ports, servers, authentication
All server details, ports and auth settings at a glance — for when you want to configure a mail client manually without scrolling through long guides.
Setting up Outlook for Mac
Connecting Microsoft Outlook on macOS to Mailcow — via IMAP, with CalDAV/CardDAV for calendar and contacts. Plus the quirks of Outlook for Mac you should know about.
Setting up the Windows Mail app and the new Outlook (Windows 10/11)
Connect the built-in Mail app in Windows 10/11 and the new Outlook for Windows 11 to Mailcow — what works, what we recommend, and what can cause privacy problems.
Setting up eM Client — Windows and macOS
eM Client is a modern commercial mail client and a good Outlook replacement — clean UI, IMAP/SMTP, CalDAV/CardDAV. Here's the setup for Mailcow.
Setting up K-9 Mail / Thunderbird on Android
K-9 Mail (now officially Thunderbird Mobile) is the most popular open-source mail client on Android. How to connect it to Mailcow via IMAP — with push via IMAP IDLE and profile import.
Using the Gmail app for your own mail address
The Gmail app on Android and iOS can also manage other IMAP accounts. How to add your Mailcow address — including a note on the privacy trade-off.
Setting up the Outlook app for Android
Connecting Microsoft's Outlook app on Android to Mailcow — via IMAP/SMTP. Why the app routes your mails through Microsoft servers, and which alternatives exist.
Setting up the stock Android mail app (Samsung, Google, Pixel)
Connect the preinstalled mail app from Samsung, Google and other Android makers to Mailcow — via IMAP/SMTP, with calendar and contacts over CalDAV/CardDAV.
Setting up Evolution on Linux (GNOME)
Evolution is the default mail app on GNOME desktops (Ubuntu, Fedora, Debian). How to connect your Mailcow mailbox with IMAP, CalDAV and CardDAV.
Setting up KMail on Linux (KDE)
KMail is the mail component of KDE PIM — the natural choice on KDE Plasma. How to connect it to Mailcow via IMAP, plus calendar and contacts through KOrganizer and KAddressBook.
Which mail client fits you? Overview and recommendation
Twelve possible mail clients and no idea where to start? Here's the clear recommendation per platform and use case — what we use ourselves, what we recommend, what we avoid.
Migrating from Microsoft 365 to Mailcow
Moving mails, calendars and contacts from a Microsoft 365 account to Mailcow — in the background, without data loss, with minimal disruption for end users.
Migrating from Google Workspace to Mailcow
Moving mails, calendars and contacts from Google Workspace to Mailcow — with IMAP migration, Google Takeout for calendars and contacts.
Migrating from a classic IMAP provider (1&1, Strato, IONOS, AllInkl, etc.)
You're switching from a classic mail host to Mailcow. How the migration works — fast and without data loss, self-service or handled by us.
Building mail reputation — so your mails actually arrive
What you can do as domain admin and user so receiving mail servers don't sink your mails in the spam folder — reputation, content, sender practice.
Switching your mail hosting plan — adjusting mailboxes and storage
Need more mailboxes, a bigger storage pool or a second domain? Here's how the plan switch works — no downtime, nothing gets lost.
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