How to Set Up IsabiMail Suite Email in Windows Mail and Outlook (Windows 10/11)
Windows is the most popular desktop operating system in the world, and chances are you want to access your IsabiMail Suite custom domain email right from your Windows PC. The good news: Windows gives you multiple ways to do this, and IsabiMail Suite works with all of them.
This guide walks you through setting up your IsabiMail Suite email account in three Windows email clients: the built-in Windows Mail app, Outlook desktop (Microsoft 365), and the new Outlook app on Windows 11. We will also cover CalDAV and CardDAV for syncing contacts and calendars, plus common troubleshooting tips.
Before You Start: Your IsabiMail Suite Server Settings
Keep these settings handy. You will need them for every client setup below.
| Setting | Value |
|---|---|
| Incoming Server (IMAP) | mailserver.isabi.email |
| IMAP Port | 993 |
| IMAP Encryption | SSL/TLS |
| Outgoing Server (SMTP) | mailserver.isabi.email |
| SMTP Port | 587 |
| SMTP Encryption | STARTTLS |
| Username | Your full email address (e.g. you@yourdomain.com) |
| Password | Your IsabiMail Suite email password |
| Authentication | Normal password (SMTP requires authentication) |
Tip: You can also use IMAP port 143 with STARTTLS, or SMTP port 465 with SSL/TLS. The settings above are the recommended defaults.
Option 1: Windows Mail App (Built-in on Windows 10/11)
The Windows Mail app comes pre-installed on every Windows 10 and Windows 11 PC. It is lightweight, fast, and supports IMAP accounts like IsabiMail Suite.
Step-by-Step Setup
- Open the Mail app from the Start menu.
- Click the gear icon (Settings) in the bottom-left corner, then select Manage Accounts.
- Click Add account.
- Scroll down and select Advanced setup.
- Choose Internet email.
- Fill in the fields:
- Email address: your full IsabiMail Suite email (e.g. you@yourdomain.com)
- User name: your full IsabiMail Suite email address
- Password: your IsabiMail Suite email password
- Account name: any friendly name (e.g. "IsabiMail Suite" or "Work Email")
- Send your messages using this name: your display name
- Incoming email server: mailserver.isabi.email
- Account type: IMAP4
- Outgoing (SMTP) email server: mailserver.isabi.email
- Check all four boxes at the bottom:
- Outgoing server requires authentication
- Use the same user name and password for sending email
- Require SSL for incoming email
- Require SSL for outgoing email
- Click Sign in.
Your IsabiMail Suite email should now appear in the Windows Mail app. Give it a minute to sync your inbox for the first time.
Option 2: Outlook Desktop (Microsoft 365 / Office)
If you use Microsoft 365 or have Outlook installed as part of Office, you can add your IsabiMail Suite account with manual IMAP configuration. Outlook desktop is a full-featured email client with calendar, contacts, and task management built in.
Step-by-Step Setup
- Open Outlook and go to File > Add Account.
- Enter your IsabiMail Suite email address and click Connect.
- If Outlook does not auto-detect the settings (it usually will not for custom domains), click Let me set up my account manually or select Advanced options > Let me set up my account manually.
- Select IMAP as the account type.
- Enter the incoming mail settings:
- Server: mailserver.isabi.email
- Port: 993
- Encryption method: SSL/TLS
- Enter the outgoing mail settings:
- Server: mailserver.isabi.email
- Port: 587
- Encryption method: STARTTLS
- Enter your IsabiMail Suite email password when prompted and click Connect.
- Click Done once Outlook confirms the account was added successfully.
Outlook will begin syncing your IsabiMail Suite mailbox. Depending on the size of your mailbox, the initial sync may take a few minutes.
Option 3: New Outlook App (Windows 11)
Microsoft is gradually replacing the legacy Mail app with the new Outlook for Windows. If you are on Windows 11 and see the toggle "Try the new Outlook" at the top of the Mail app, or have already switched, here is how to add your IsabiMail Suite account.
Step-by-Step Setup
- Open the new Outlook app.
- Click the gear icon (Settings), then go to Accounts > Email accounts > Add account.
- Enter your IsabiMail Suite email address and click Continue.
- The new Outlook may attempt auto-discovery. If it does not find settings automatically, select IMAP.
- Enter the IMAP and SMTP settings:
- IMAP server: mailserver.isabi.email, Port 993, SSL/TLS
- SMTP server: mailserver.isabi.email, Port 587, STARTTLS
- Enter your password and click Continue.
- Click Done to complete the setup.
Note: The new Outlook syncs email through Microsoft's cloud. If you prefer a direct IMAP connection without Microsoft as a middleman, consider using the classic Outlook desktop or another client like Thunderbird.
CalDAV and CardDAV: Sync Contacts and Calendar
IsabiMail Suite supports CalDAV (calendar) and CardDAV (contacts) protocols, which means you can sync your IsabiMail Suite calendars and address books to your desktop. However, the built-in Windows Mail and Calendar apps do not natively support CalDAV or CardDAV.
Here are your options for syncing calendars and contacts on Windows:
Outlook Desktop with CalDAV/CardDAV Plugin
Outlook desktop does not natively support CalDAV or CardDAV, but you can add support with a free plugin:
- Install CalDAV Synchronizer (free, open-source Outlook add-in).
- After installation, open Outlook and go to the CalDAV Synchronizer tab.
- Click Synchronization Profiles > Add new profile.
- Select Generic CalDAV/CardDAV.
- Enter the server settings:
- CalDAV URL: https://mailserver.isabi.email/dav/calendars/
- CardDAV URL: https://mailserver.isabi.email/dav/addressbooks/
- Username: your full IsabiMail Suite email address
- Password: your IsabiMail Suite email password
- Click Test to verify the connection, then OK to save.
Your IsabiMail Suite calendars and contacts will now sync with Outlook alongside your email.
IsabiMail Suite
You can also manage calendars and contacts directly in your IsabiMail Suite webmail at mailserver.isabi.email. The webmail includes a full calendar and contacts manager accessible from any browser, with no extra setup needed.
Troubleshooting Common Issues
"Cannot connect to server" or login fails
- Double-check your username is your full email address (e.g. you@yourdomain.com), not just the part before the @.
- Verify the password. If you recently changed it in IsabiMail Suite webmail, update it in your Windows client as well.
- Ensure you are using the correct ports: 993 for IMAP (SSL/TLS) and 587 for SMTP (STARTTLS).
Emails send but are not received
- Confirm your domain's DNS records (MX, SPF, DKIM) are configured correctly. You can check this in your IsabiMail Suite dashboard under domain settings.
- Check the recipient's spam folder.
- Make sure SMTP authentication is enabled in your client settings.
Slow sync or missing folders
- The first sync can take a few minutes, especially with a large mailbox. Be patient.
- In Outlook, go to File > Account Settings > Account Settings > select your IsabiMail Suite account > Change. Under "Mail to keep offline," select All to sync your entire mailbox.
- In Windows Mail, ensure your sync frequency is set to "As items arrive" under account settings.
"Outgoing server requires authentication" error
- In Windows Mail, make sure the checkbox for "Outgoing server requires authentication" is enabled.
- In Outlook, go to outgoing server settings and ensure "My outgoing server (SMTP) requires authentication" is checked, with "Use same settings as my incoming mail server" selected.
New Outlook privacy concern
- The new Outlook for Windows routes email through Microsoft's servers. If this is a concern for your business, use the classic Outlook desktop app or Thunderbird instead, both of which connect directly to IsabiMail Suite via IMAP without any intermediary.
Which Windows Email Client Should You Use?
| Client | Best For | CalDAV/CardDAV |
|---|---|---|
| Windows Mail | Quick, lightweight email checking | Not supported |
| Outlook Desktop | Full productivity (email + calendar + contacts) | Via CalDAV Synchronizer plugin |
| New Outlook | Modern interface, Microsoft integration | Not supported natively |
| IsabiMail Suite | Zero setup, full features from any browser | Built-in |
For most users, Outlook desktop with the CalDAV Synchronizer plugin gives you the most complete experience: email, calendar, and contacts all in one app. If you want the simplest path with no installation, IsabiMail Suite webmail at mailserver.isabi.email has everything built in.
Get Started
Setting up IsabiMail Suite on Windows takes about 5 minutes. Whether you use the built-in Mail app, Outlook, or the new Outlook, the process is straightforward once you have the server settings. If you do not have a IsabiMail Suite account yet, create your free account and get a professional email address on your own custom domain in under 2 minutes.