How TrekMail Webmail Works: Architecture and Security

TrekMail webmail is a custom-built email client — it is not based on Roundcube or any other open-source webmail package. We built it from scratch to give you a faster, more integrated experience that fits naturally alongside everything else in your TrekMail account.

Note: If you used TrekMail before 2025, you may have seen the legacy webmail at /webmail-old/. That older interface is still accessible but is no longer the primary client. The new webmail at /webmail/ is where all new features are developed.

What powers the webmail

The interface is a single-page application — meaning the page loads once and updates dynamically as you navigate, click, and compose. This is why switching folders, opening messages, and loading the compose window feel instant rather than triggering a full page reload.

The rich text editor used for composing emails supports full formatting — bold, italic, lists, inline images, links, code blocks, and more. It handles everything from a quick one-liner to a properly formatted business email.

How your mailbox connection works

When you log in to webmail, TrekMail connects to your mailbox using your email address and password. Your credentials are used to authenticate against your mailbox directly — the same credentials work in any standard email client like Outlook, Apple Mail, or Thunderbird.

Webmail communicates with your mailbox over a secure, encrypted connection. Your password is never stored by the webmail client itself.

White Label routing: Accounts with White Label Lite active serve the same webmail from their branded domain (app.yourbrand.com) instead of trekmail.net. The experience is identical — the only difference is the URL, SSL certificate, logo, name, and colours. Mailbox setup in external email apps (IMAP and SMTP) continues to use TrekMail's hostnames.

Where your data lives

Because drafts and sent mail use standard IMAP folders, anything you do in webmail is immediately visible in any other email client connected to the same mailbox — and vice versa.

Sessions and security

Your webmail session is separate from your TrekMail dashboard session. Logging out of the dashboard does not log you out of webmail, and logging out of webmail does not affect the dashboard.

Sessions expire automatically after a period of inactivity. On shared or public computers, always use the Log out option when you are finished rather than simply closing the browser tab.

If two-factor authentication (2FA) is enabled for your webmail account, you will be asked for a one-time code every time you log in from a new session. See the 2FA guide for setup instructions.

Spam filtering and email authentication

Incoming mail is scanned for spam before it reaches your inbox. If you mark a message as spam or as not spam inside webmail, that feedback is used to improve filtering for your mailbox over time.

When you receive a message from a sender whose images are blocked by default, a banner appears at the top of the message. You can click Show images once to display them for that message only, or Always show from this sender / Always show from this domain to add them to your trusted senders list. Trusted senders are stored per-mailbox and can be managed from the Settings drawer.

You can read more about spam controls and the sender authentication badges (DKIM, SPF, DMARC) that appear on incoming messages in the spam and security guide.

Calendar invitations

When you receive an email containing a calendar invitation, TrekMail webmail shows Accept, Tentative, and Decline buttons directly on the message. Clicking one sends a calendar reply email back to the organiser and records your response inline on the invitation, so you always know how you replied.

Calendar and contacts sync

TrekMail exposes your calendar and address book over CalDAV and CardDAV — the same open standards Apple and Google use for their own services. Any standards-compliant client (Apple Calendar/Contacts, iOS, Android via DAVx⁵, Thunderbird/TbSync) can connect at trekmail.net using your mailbox email and password and sync events and contacts both ways. Outlook does not support CalDAV natively — see the Outlook guide for the workaround.

Language support

TrekMail webmail is available in 13 languages: English, Spanish, French, German, Portuguese, Italian, Dutch, Russian, Chinese, Japanese, Korean, Arabic, and Hebrew. The interface automatically uses the language you have selected in your mailbox settings. Right-to-left (RTL) layout is applied automatically for Arabic and Hebrew.

Browser and device compatibility

TrekMail webmail works in all modern browsers: Chrome, Firefox, Safari, Edge, and their mobile equivalents. It is fully responsive and adapts to phone and tablet screen sizes.

For the best experience on mobile, you can also install webmail as a Progressive Web App (PWA) — this gives you an app icon on your home screen and a fullscreen experience without the browser address bar. See the mobile and PWA guide.