Frequently Asked Questions


1. Email

1.1. What is the difference between POP and IMAP?

  • POP (or POP3) is the Post Office Protocol. POP clients download mail from you mailbox into your mail client (e.g. Outlook, Thunderbird), and (usually) delete the original messages from the server. Folders are local to your mail client, and WebMail can only see the un-downloaded mail. If you create a new folder using WebMail or an IMAP client, you will not be able to download messages from it using POP.
  • IMAP is the Internet Mail Access Protocol. IMAP clients keep all the mail on the server, although they may make local copies to speed up access. You can access all your IMAP folders from several IMAP clients or from WebMail.

1.2. What are the mail server addresses?

  • The SMTP relay server (for sending outbound mail) is called “”. It can be contacted on the normal default port 25, the “submission” port 587 or the TLS port 465. Note that the latter requires the use of SSL security.
  • The POP protocol for downloading mail from your inbox to your computer is available at “”, on the default port 110, and the secure port 995.
  • The IMAP protocol for accessing your mailbox and folders is available at “”, on the default port 143 and the secure port 993.

1.3. I’m using another provider, and can not send mail out via “”. How can I send my mail?

  • Most likely, the provider is filtering outbound email traffic. Some providers do this so that computers compromised by viruses or other malware can not be used to send out unsolicited email (aka spam). To bypass these filters, configure your email client to use port 587 instead of the default port 25. Note that you may need to look in the advanced settings of your mail account setup in your email client to change the outbound mail (SMTP) port number.
  • If you can’t change the outbound server, you may need to use your provider’s SMTP server, or you can use WebMail to send messages.

1.4. I get a “relaying denied” message sending email through Why?

  • If Knossos is not your Internet access provider, you need to authenticate with the SMTP server. For Outlook Express, tick the box marked “my server requires authentication” under “Servers” in the account properties (under the Tools / Accounts menu). Note: do not check a box marked “Log on using Secure Password Authentication”.

1.5. I’m getting authentication errors.

  • Make sure you use your full mailbox name as your username, i.e., not just myname.
  • Passwords are case sensitive. Beware the Caps Lock key.
  • Each mailbox has its own password. Don’t confuse these, or confuse it with your web site password.

1.6. How can I use WebMail?

  • Browse to¬† Use your full email address (i.e. as your username, and you email password for the password.

1.7. Do you filter viruses or spam?

  • Yes. Email messages containing known viruses and worms (and some banking scam emails) are blocked by our mail server before it is forwarded to your mailbox. Note that some viruses spread as email place themselves in encrypted or password protected archive files (e.g. ZIP files); these can not be decrypted and scanned by the virus scanner. Typically, the text of such a message will provide the password and implore you to open it. Do not open a password protected attachment if you are not expecting it.
  • Junk email (spam) is filtered by our inbound servers. The servers assign a “score” to each message. Messages that have a very high probability of being spam are simply rejected by our servers. Messages with a lower score but very likely spam are marked as [SPAM] in the subject header, and are automatically filed in the Junk folder of your mailbox.
  • Note that the filters can’t get everything. Be especially careful about messages with attachments, particularly if it is from someone you don’t know or aren’t expecting mail from.

1.8. How can I get to my Junk folder?

  • If you are using IMAP or WebMail, the Junk folder should appear on your folders list. Note that it is only created the first time you receive junk email. If you are using POP, the Junk folder is not downloaded, so you will need to use WebMail to see what is in the Junk folder.
  • If the Junk folder does not appear automatically on your IMAP client, you may need to refresh your folders list for your client to pick it up.

1.9. Can I filter email on the server?

  • Yes. The WebMail interface includes a “Filters” item on the menu bar, which allows you add filtering rules to your inbound email. Rules can select messages by the contents of various message headers, the message body or even the size of the message, and rule actions include filing messages into different folders, marking them as read, forwarding to other users etc. There is also a blacklist and whitelist feature, and a “Vacation” feature to allow users to be notified if you are going to be unable to read your email for a while.

1.10. What about encryption?

  • Our POP, IMAP, WebMail and SMTP outbound servers all support encryption (SSL/TLS). At present these use self-signed certificates, so you will need to confirm that the certificates are acceptable (click on the “Accept this certificate permanently” button when asked).
  • Note that email beyond your own computer and Knossos servers may be transmitted in clear text, as many email servers do not support encryption or have problems with negotiating an encrypted connection.