Is there a specification defines INBOX as the primary folder?

Question

I just play with emails recently. An application downloads email from mail server with apache-camel-mail component via IMAP protocol and do some magic with the email body.

The problem I observe is about primary email folder name on Lotus notes email server. It supposed to be INBOX but actually it is Inbox.

My question is...

Is there a specification for IMAP or email in general to define the primary folder as INBOX? Or I can hypothetically used in my fresh new mail server primary inbox name like 1nB0x with no harm and still be compliant to IMAP spec.

Thanks

Answer 1

From RFC 3501 (IMAP version 4rev1):

The case-insensitive mailbox name INBOX is a special name reserved to mean "the primary mailbox for this user on this server". The interpretation of all other names is implementation-dependent.