EMail Policy at HLRN

— Policy for Email to Addresses in the Domain —


Important: HLRN wants to hear from you, and HLRN wants to get your email.

The problem of increasing levels of unwanted "spam" email has forced HLRN to implement measures to protect HLRN email addresses against spam.

Email Policy at HLRN

The measures are based on the following policy.

Email addresses in the domain

  • may only be used for communication with HLRN and for HLRN related purposes only,
  • only serve as addresses for internal purposes,
  • only serve as list addresses for groups of users or members of HLRN,
  • have no mailboxes associated with them and are used for forwarding purposes only.

Therefore all email addresses in the domain must be known to the mail server and an alias (forwarding address) must be defined for these.

Email Address Validity

All users or members of HLRN must own at least one valid email address outside HLRN as their main mailing address. HLRN requires this to be a personal address in the institute, university or research organization they are affiliated with. This address must be made known to HLRN during the application for an account. It identifies the user as a valid user of HLRN and must be used as sender address for all mail to addresses in the domain.

HLRN will reject applications for new user accounts that have registered non-compliant email addresses, e.g. from email providers at (but not limited to) Google/gmail, Yahoo,, GMX, Hotmail, AOL, Outlook, and such. Contact HLRN user administration if you are unable to comply with the policy, but still require an HLRN account.

So be sure to use the email address you stated during application when contacting addresses.

HLRN reserves the right to close an account immediately, when its registered email address becomes invalid (e.g. email is undeliverable).

Email Address Changes

When your main email address has changed for some reason, but you are still a user of HLRN, you should contact your HLRN consultant or HLRN user administration to get your entry in our database modified. If email to a registered address is undeliverable, HLRN administration will disable the respective user accounts.

Purpose of Email

All email not concerning HLRN business must be directed to the non-HLRN email address(es) of the intended recipient(s).

Email to HLRN addresses may not be used to distribute defamatory, fraudulant or harrassing messages, or otherwise to engage in any illegal or wrongful conduct. The restrictions for email to or from HLRN addresses include, but are not limited to the following.

  • Email must not violate any rights, laws, policies or guidelines.
  • Email must not contain any viruses or other malicious software
  • Email must not have unwanted commercial or pornogaphic content, commonly known as "spam".

Anti-Spam Measures

In order to enforce the above policy HLRN has taken the following measures:

  • Relaying is not allowed.
  • We block email from certain hosts, domains, and addresses that are listed in several reputable spam blacklists.
  • We block email from hosts or domains, that are unknown to the Domain Name Service (DNS).
  • We may approve or disapprove email from unknown hosts/addresses before delivery to the intended recipient(s).
  • We block email with executable attachments that are potentially malicious (e.g. .pif, .exe, .bat, .com, .vbs).
  • We scan the content of all mails using "SpamAssassin" and mark potential spam appropriately as such.
  • We dismiss any email sent from the inside of if the sender address is unknown to the mail server.

We constantly refine the measures we use, to make sure we find just the right combination of spam protection that protects HLRN and our users from most unwanted mail, yet does not block out the mail we want to get.

You Have Problems Emailing HLRN?

If your email is being rejected by our server, you will get a message that says something like "Client host rejected: cannot find your hostname ..." or "Client host [] blocked using ... "

Here is the list of blacklists HLRN is currently using for spam blocking:

If you are unable to send email to HLRN, talk to your internet service provider (ISP) or system administrator. Your host or mail server is probably listed in one of these blacklists or it may be misconfigured.

And while it is your ISP's or system administrator's job to take care of things like this, if you have no luck with them, please contact your HLRN consultant or call us (see the HLRN contact page) and we may be able to adjust our mail server to allow receiving mail from you.

Because, as already mentioned, HLRN wants to hear from you!

Thank you.

Created by WolfgangBaumann

Last modification: WolfgangBaumann - 21 Feb 2018 15:54 / 2 years, 5 months, 3 weeks ago. (Version: 8)

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