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Courier Imapd Server

O

Oliver Block

Guest
Hello everybody,

I'd like to ask a question regarding Courier Imapd which is the Imap Daemon that Plesk relies on.

As Courier Imapd uses the '.' (dot character) as hierarchy delimiter there are problems with dot characters within mailbox paths. On the other hand, courier imap uses the email address of the user as part of the hierarchy, especially with shared folders. Let me give an example:

This is the folder hierarchy for personal mailboxes:

INBOX.Inquiries.Customers

or as tree:
Code:
+-- INBOX
    |
    +-- Inquiries
       |
       +-- Customers

Let's assume an imap user will create a shared folder, i.e. a mailbox that is accessible from other users, too. The typical hierarchy looks like this:

Code:
+-- #shared
      |
      + sales@company com
          |
          +--  Inquiries
                 |
                 +-- Customers

Every imap user that logs into courier imap and that was granted the required privileges can access the folder

"#shared.sales@company com.Inquiries.customers"

Shared folders are common for other imap servers, too.

Unfortunately shared folders are a real weakness of courier imapd and creating them is a real pain, because courier imapd gives almost no debug information when something goes wrong. Another real problem is that the "." (dot character) is used as hierarchy delimiter, just as "/" in Unix and "\" in windows.
Now, if the user wants to create a personal mailbox in his Mail Programm which you can do quite easily with every mail program, you have a real problem if you try to create a shared folder/mailbox from the client side.
Courier imap ships a readme file that explains how to create so called virtual shared folders and if you are lucky it even works. On file system level these are folders that are underneath the folder hierarchy but have set special access rights to other imap users. That makes them visible for the owner underneath the INBOX hierarchy and for others underneath the #shared hierarchy.

Is it possible in Plesk to switch from qmail and courier to e.g. cyrus and postfix?

Best Regards,

Oliver Block
 
Hello Oliver,

There are two Message Transfer Agents (MTA) supported by Parallels Plesk Panel version 9, they are Qmail and Postfix.

The following Knowledge Base article describes how to switch between them:

[How to] How to define what MTA is used in Parallels Plesk Panel and how to switch from Qmail to Postfix and vice versa?
http://kb.odin.com/en/5801

Regards,
Denis
 
Courier Shared folders

Hello!

I'm fine with courier and qmail, but I like enable shared folders.


Anyone has experience to shared folders with courier?


Thanks!
 
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