IMAP versus POP3: which should you choose?
Choose the right protocol for your workflow and avoid missing messages or inconsistent folders across devices.
Before you start
- The number of devices you use
- The mailbox storage limit
- Your offline access needs
- A backup before changing an existing setup
Understand IMAP
IMAP keeps messages on the server and synchronizes read state, deletion, and folders across Webmail, phones, and computers.
One mailbox • All devices
Understand POP3
POP3 downloads messages to one device and may remove them from the server, depending on configuration.
Download to one device
Choose IMAP for most teams
ROT4 recommends IMAP for business use because it keeps multiple devices and Webmail synchronized.
Recommended: IMAP + SSL/TLS
Monitor mailbox storage
IMAP keeps messages on the server, so archive large messages and review quota regularly.
Monitor quota + archive
Common troubleshooting
| Issue | Solution |
|---|---|
| Messages differ between devices | Confirm every device is using IMAP. |
| The mailbox is full | Remove large messages, raise quota, and empty Trash and Junk. |
| Old email exists on one computer only | Export it locally and import it into the IMAP mailbox when needed. |
Need help?
Send the error screenshot and service name to ROT4 support and we will help you complete the setup safely.
