Microsoft has rebuilt the mail setup on Windows several times in recent years. We explain the two current options — and say in plain terms when you’re better off reaching for classic Outlook or Thunderbird.
Overview of mail apps on Windows
| App | Our assessment |
|---|---|
| Classic Outlook (2019/2021/365) | Works solidly. See Outlook Windows. |
| Mail app (Windows 10/11) | Being phased out by Microsoft, replaced by the new Outlook. Still works, but a dead end. |
| New Outlook (Windows 11) | Web view, routes mail through Microsoft servers. Privacy concerns. |
| Thunderbird | Best open-source alternative — see Thunderbird. |
From our experience: for serious use we recommend classic Outlook or Thunderbird. The stock Windows Mail app and the new Outlook do work, but they have weaknesses.
Stock Mail app (Windows 10 and Windows 11)
The app is simply called “Mail” and is installed on every Windows. It’s being phased out gradually since 2024, but still runs.
Setup
- Open the Mail app → if there are no accounts yet: the setup dialog appears. Otherwise: Accounts → Add account.
- Choose Advanced setup.
- Select Internet email.
- Fill in the fields:
| Field | Value |
|---|---|
| Email address | full mail address |
| Username | same |
| Password | mailbox / app password |
| Account name | your choice |
| Send your messages using this name | display name |
| Incoming server type | IMAP4 |
| Incoming mail server | mail.xaweho.de:993 |
| Outgoing mail server (SMTP) | mail.xaweho.de:587 |
| Require SSL (incoming) | enabled |
| Require SSL (outgoing) | enabled |
| Require authentication (outgoing) | enabled |
| Use the same credentials | enabled |
Sign in.
Quirks
- New mail arrives delayed: the app only fetches IMAP accounts at an interval (15+ minutes, adjustable in the account). Clients with IMAP IDLE — Thunderbird or classic Outlook — show new mail near-instantly instead.
- No Sieve filters: local rules exist, but very limited.
- No PGP/S/MIME: encrypted mail needs a solution outside the app.
From our experience: for casual users with one mailbox, the Mail app is enough. For pro-level needs, better classic Outlook or Thunderbird.
New Outlook (Windows 11)
Since 2023 Microsoft has been developing a “new Outlook” as the replacement for the Mail app and (long-term) classic Outlook too. It’s a web view — meaning: the app is a browser under the hood, and mail is routed through Microsoft cloud endpoints.
What that means
If you set up a third-party account like your xaweho Mailcow in the new Outlook, Microsoft routes your mail traffic through its servers. So Microsoft sees:
- Who you communicate with
- Content (to a limited extent, anonymized)
- Mail behavior (when, how much)
That’s a privacy issue, which Microsoft communicates openly (buried in the terms). For accounts whose whole point is GDPR-compliant hosting (which is central for many of our Mailcow customers) — a problem.
Setting it up anyway
If you want to try it regardless:
- Open the new Outlook.
- Add Account → enter your email address.
- Microsoft asks: “Where are these messages stored?” → choose IMAP.
- Server data:
| Field | Value |
|---|---|
| IMAP server | mail.xaweho.de:993 |
| SMTP server | mail.xaweho.de:587 |
| Encryption | SSL/TLS for IMAP, STARTTLS for SMTP |
| Username | full mail address |
| Password | mailbox / app password |
Add. Microsoft now fetches your mail and stores it in its cloud.
Our recommendation
If you like the new Outlook look and feel but don’t want Microsoft routing:
- Thunderbird — modern UI since version 115, capable, open source.
- Classic Outlook 2021/365 — no web routing, all data local.
- eM Client — commercial mail client with a modern look.
Classic Outlook is the better choice
If you have a Microsoft 365 license (or bought Office 2021/2024), classic Outlook is still available and the better path for third-party accounts. The apps often sit side by side in the Start menu — one is called “Outlook”, the other “Outlook (new)” or “Outlook (classic)”.
Setup for classic Outlook: see Setting up Outlook on Windows.
Frequently asked questions
The Mail app says “Unable to connect to server” Usually a typo in server, port or SSL setting. Type all values in again manually, no copy-paste. As a last resort, delete the account and create it fresh.
How do I switch back from the new Outlook to the classic one? In the top right corner of the new Outlook there’s a “Try the new Outlook” toggle — if it’s on, you can switch it back. That puts you back in classic Outlook.
Microsoft keeps pushing the new Outlook — is classic Outlook going away soon? Microsoft officially says classic Outlook stays supported until at least 2029. In practice it will probably live longer — many enterprise customers refuse to move to the new Outlook.
Do I need an app password for the Mail app? With 2FA active: yes. The Mail app can’t do anything with TOTP. See App passwords.
What about Windows Live Mail? Windows Live Mail has been unsupported since around 2017 and shouldn’t be used anymore. If it’s still in use: switch urgently to Outlook or Thunderbird.
How do I get calendar and contacts in sync on Windows? Via CalDAV/CardDAV against SOGo. In classic Outlook, the free CalDav Synchronizer plugin handles that; Thunderbird speaks CalDAV/CardDAV directly. The Windows Mail app and the new Outlook can do neither against our server — one more reason to switch.
What’s next
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.