How to Setup a Complete Mail Server (Postfix) using ‘SquirrelMail’ (Webmail) on Ubuntu/Debian

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Aaron Kili

Aaron Kili is a Linux and F.O.S.S enthusiast, an upcoming Linux SysAdmin, web developer, and currently a content creator for TecMint who loves working with computers and strongly believes in sharing knowledge.

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179 Responses

  1. Ashok.S says:

    i didn’t get any ssl configuration window while installing dovecot

  2. Sushant Joshi says:

    I have configured almost everything and also the mail is working perfectly fine but my question is can’t we install squirrel administrator for managing all the users using web ui ?

    • Ravi Saive says:


      You can install Squirrelmail as explained in this article: .

    • Chael Gutierrez says:

      Hello, @Sushant

      Based on my previous setup of email servers through this tutorial. I haven’t found any web UI for managing squirrel mail users.

      What I done is build a simple web UI and API using nodejs for CRUD users.

  3. Chael Gutierrez says:

    Hello this might help you.

    I created this document based on this tutorial.

  4. static z says:

    I’m unable to launch squirrel-email web UI, any help ?

  5. Dave says:


    Many thanks for sharing this article.

    However, my major problem is how to point the dns to enable it work. For example, i purchased my domain from, what configuration must i do at the domain provider’s site?
    And, how can I set up the following:


    I have an account with, where I have also created a droplet and have an IP for my domain. I have created a new record at and I have changed the dns server information at as and

    I have already setup Postfix Mail Server on my Ubuntu 14, although, without installing the squirrel mail, but while i was researching how to fix the above, i came across this post and i find it very helpful because I was able to add Squirrel Mail to my Postfix Mail, but still, nothing is working.

    Please I really need your help to fix this.

    • Ravi Saive says:


      In your domain control panel, point your domain A and MX records to your server IP address where Postfix installed.

  6. Madan says:

    Hello All,

    I am not able to get to the web interface, page fails to load. Please help.

  7. faisal says:

    add the user to the mail group, this will resolve the inbox issue:

    # adduser user group
  8. Adnan says:

    Hi ,

    When I try to send any mail I got an error like:

    “Service not available, closing channel
    421 4.3.0 collect: Cannot write ./dfwAKAhJ3f108965 (bfcommit, uid=0, gid=119): No such file or directory”

    Is there anybody give me a hand to rid out of it .


  9. James Arnold says:

    Hi Zac, I still have the error even though I added my user to the mail group. From my /var/llog/mail.err, I am getting this:

    localhost dovecot: imap(myusername): Error: Opening INBOX failed: Mailbox isn’t selectable

  10. Adriano Machado says:


    During the installation of Dovecot did not execute the creation of SSL keys, how do I create at this time?

    Another thing, following step by step, I still have a problem logging in to squirrelmail: ERROR: Connection dropped by IMAP server.

    Can you help me?

    Thank you.

    • Have you checked the log at /var/log/mail.err?

      Maybe the permission or the existence of the folder is missing in /var/mail/myusername?

      I still have the error though on localhost dovecot: imap(myusername): Error: Opening INBOX failed: Mailbox isn’t selectable.

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