When setting up your email client, you often have to choose between IMAP and Exchange (or EAS). These protocols define how your email client communicates with the server. Understanding their differences is essential, especially when migrating to a new hosting provider like Infomaniak.
Quick overview
| Feature | IMAP | Exchange (EAS) |
|---|---|---|
| Type | Open protocol (standard) | Proprietary protocol (Microsoft) |
| Email storage | Server | Server |
| Synchronization | Emails only | Emails + Calendar + Contacts + Tasks |
| Push notifications | Via IDLE (partial) | Native |
| Support | Universal | Limited (Microsoft, select apps) |
IMAP: the universal protocol
What is IMAP?
IMAP (Internet Message Access Protocol) is an open standard protocol created in 1986 and widely adopted. It allows you to access your emails stored on a server from any email client.
How IMAP works
- Your emails remain on the server
- Your email client downloads headers and then content on demand
- Changes (read, delete, move) are synced with the server
- All your devices see the same mailbox state
IMAP advantages
- Universal compatibility – Works with every email client
- Open standard – No vendor dependency
- Multi-device access – PC, Mac, mobile, webmail
- Easy migration – Simple IMAP-to-IMAP copy
IMAP limitations
- Handles emails only (not calendar or contacts)
- Push notifications less responsive than Exchange
- Requires CalDAV/CardDAV for calendar and contacts
Exchange: the Microsoft ecosystem
What is Exchange?
Exchange is Microsoft\'s email server. Exchange ActiveSync (EAS) is the proprietary protocol that enables synchronization with clients. In common usage, "Exchange" often refers to both.
How Exchange works
- All-in-one synchronization: emails, calendar, contacts, tasks
- Instant push for new emails
- Advanced permission and sharing management
- Enterprise features (retention, eDiscovery, etc.)
Exchange advantages
- All-in-one – A single account to sync everything
- Instant push – Real-time notifications
- Perfect Outlook integration – Built for Microsoft
- Enterprise features – Advanced sharing, compliance
Exchange limitations
- Proprietary Microsoft protocol
- Limited support outside the Microsoft ecosystem
- Expensive licenses
- More complex migration to other systems
What about POP3?
POP3 is an older protocol that downloads emails to your device and (optionally) deletes them from the server. It\'s discouraged today because:
- No synchronization between devices
- Risk of data loss
- Not suited to modern multi-device usage
Our advice
Only use POP3 if you have a specific reason (local archiving, technical constraint). Otherwise, prefer IMAP.
IMAP + CalDAV/CardDAV: the alternative to Exchange
To get the same features as Exchange with open protocols, combine:
| Function | Exchange | Open alternative |
|---|---|---|
| Emails | Exchange/EAS | IMAP |
| Calendar | Exchange/EAS | CalDAV |
| Contacts | Exchange/EAS | CardDAV |
| Tasks | Exchange/EAS | CalDAV (tasks) |
This is exactly what Infomaniak offers: a combination of standard protocols that provides the same features without Microsoft dependency.
What protocol does Infomaniak use?
Infomaniak uses open standard protocols:
- IMAP for emails
- SMTP for sending emails
- CalDAV for calendars
- CardDAV for contacts
Advantages of this approach
- Compatible with every email client on the market
- No vendor lock-in
- Migration to/from any standard service
- Native support on iOS, Android, Mac
Outlook for Windows configuration
Outlook for Windows does not natively support CalDAV. To sync calendars and contacts, install the free CalDAV Synchronizer plugin (see our dedicated guide).
Impact on migration
From Exchange to IMAP (Infomaniak)
- Emails – Simple IMAP migration, automatable
- Calendar – ICS export then CalDAV import
- Contacts – VCF export then CardDAV import
- Client configuration – New account to set up
From IMAP to IMAP
The simplest migration. Automatic migration tools are available.
Final comparison
| Criterion | IMAP (+CalDAV) | Exchange | Winner |
|---|---|---|---|
| Compatibility | Excellent | Limited | IMAP |
| Ease of setup | Simple | Simple (Outlook) | Tie |
| Push notifications | Good (IDLE) | Excellent | Exchange |
| Outlook integration | Requires plugin | Native | Exchange |
| Independence | Total | Microsoft dependency | IMAP |
| Cost | Variable | Microsoft licenses | IMAP |
| Sovereignty | Free choice | USA (Microsoft) | IMAP |
Conclusion
Exchange offers an appealing all-in-one integration, especially for companies already in the Microsoft ecosystem. But that convenience comes at a cost: vendor dependency, data in the USA, and expensive licenses.
IMAP + CalDAV/CardDAV delivers the same experience with standard protocols, freedom to choose your hosting provider, and true sovereignty over your data. This is the approach chosen by Infomaniak and by everyone who wants to stay in control.
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