Humboldt-Universität zu Berlin - Computer and Media Service

Addresses, Ports, Quick Start Guide

  • IMAP is only supported with TLS.
  • IMAP-IDLE/NOTIFY and Push are not supported.

Email configuration

  • Incoming mail server/Imap server
    • mailbox.cms.hu-berlin.de
    • Port 993 (TLS)
    • Authentication method: normal/password
    • Username: Your HU-Account
    • Certificate fingerprints:
      • SHA1: 6E:FC:50:54:3B:B4:0F:C2:D1:6B:3D:D0:67:E3:CE:1D:9C:E8:C0:39
      • SHA256: E7:49:BF:AF:49:52:A1:75:56:7E:14:F2:B3:3D:9D:AA:9D:96:DC:C3:E7:75:13:4B:AE:6B:B8:4A:23:23:37:FF
    • If port 143 is entered during the initial installation, please change the respective setting to the default TLS port 993 afterwards.
    • Leave the setting "Check for new messages every... at the default value of 10 minutes to avoid unnecessary load on the server.
    • "My" IMAP server: Account Info
  • Outgoing mail server/SMTP server
    • mailhost.cms.hu-berlin.de
    • Post 587 (StartTLS)
    • Authentication method: normal/password
    • Username: Your HU-Account
  • Please note:
    On Telekom routers, the HU's outgoing mail server may have to be marked as "allowed mail server", otherwise it might be blocked. (see also: Telekom hilft [German])
  • Personal settings
    • HU-Account: usually 8 characters long,
      e.g.: muellere (or older HU-Accounts with numbers: h0444xyz)
    • Email address: as provided, e.g.: erika.mueller@hu-berlin.de
    • Please only save your password using a master password for your email client, otherwise it will be save unencrypted!
  • Filter spam
    • Enter a filter for the header line "X-Spam-Flag" with the value "YES" in your e-mail program.
    • Alternatively, have the mail server sort these mails to the "AutoCleanSpam" folder.
      To activate the automatic option, you need to sign a one-time declaration of consent in which you agree to the automatic deletion of spam e-mails from your personal folder "AutoClean-Spam" after a period of 12 weeks (fvf-Website, German).

Resources, constraints

  • Inbox and folders
    • There are no limitations on mailbox size, we do however reserve the right to introduce a quota.
    • Still, the inbox should not be used as an archive, as each email stored there slows down access. Set up an "Inbox-Open" folder and move the messages from the inbox to it.
    • Email programs sometimes have problems to handle several 10,000(!) emails. Therefore, we recommend structuring your mailbox using folders/subfolders.
  • Sending emails
    • Direct sending via port 587:
      From within the HU network, external SMTP servers are only accessible via port 587. Please check in advance whether your email provider offers sending mails via port 587.
    • Direct sending via port 25 and 465:
      From within the HU network, external SMTP are not accessible via port 25 or 465.
  • Relay/SMTP server mailhost.cms.hu-berlin.de
    • Email size (sending/receiving): maximum 20 MByte
      • Using the CMS mailing list server (Sympa): maximum 5 MByte
    • Recipients per email: maximum 100
    • Please note that other mail servers involved in the mail transfer may enforce other restrictions.
  • Addressing, email address LDAP
    • Accesss to email addressess from ZIS is allowed in the local network of HU or via VPN.

Additional restrictions

  • POP3 is not supported.
  • Email clients have to support at least TLSv1.2.

Email backup

  • IMAP server
    • All Imap server are backed up once per hour. Hourly snapshots are available for 7 days.
    • In addition, daily backups are available for 60 days.
  • Restoring deleted or "lost" emails is very labour-intensive. Please be cautious when handling multiple emails at once and take care not to accidentally move or delete them. The same applies for folders.