Understand the three jobs
IMAP synchronizes a mailbox with the server and is usually convenient when you read mail on several devices. POP downloads messages according to the client’s retention settings; messages may exist only on that computer. SMTP sends outgoing mail. A working incoming connection does not prove SMTP is configured correctly.
Match the entire configuration
- Identify the actual mailbox provider, including any completed migration.
- Copy its hostname, port, encryption and authentication method as a set.
- Use the complete username format the provider specifies.
- Send and receive a test message and compare folders with webmail.
Common secure ports are a reference, not a setup recipe
| Protocol | Common encrypted port | Important limit |
|---|---|---|
| IMAP | 993, implicit TLS | Provider must support it |
| POP3 | 995, implicit TLS | Check local-mail retention |
| SMTP | 465 implicit TLS or 587 STARTTLS | Match provider authentication |
Do not disable encryption to make an error disappear. Some services require OAuth, a bridge application or their own client instead of ordinary manual settings.
Explore provider-specific guides for official configuration references.