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EX2016 - Block external senders from sending to contacts RRS feed

  • Question

  • Hello everyone,

    For distribution groups you can require that all senders are authenticated, is there any way to configure the same requirement for contacts?

    The scenario is that we have a regular user mailbox and a contact that have very similar names. While the primary address of the contact is external, they also have very similar internal email addresses based on the email address policy.

    When an external 3. party tries to send an email to our regular user mailbox they type in the wrong address and send it to the internal email address of the contact. When this happens Exchange will automatically forward that email to the primary email address of the contact, which is an external domain.

    We have changed the internal email addresses of the contact to avoid the problem, but in general we would like to block all external senders from sending to our contacts as this could lead to information leakage or possibly even be exploited by malicious users.(?)


    Friday, February 23, 2018 10:28 AM

Answers

  • Hello everyone,

    For distribution groups you can require that all senders are authenticated, is there any way to configure the same requirement for contacts?

    The scenario is that we have a regular user mailbox and a contact that have very similar names. While the primary address of the contact is external, they also have very similar internal email addresses based on the email address policy.

    When an external 3. party tries to send an email to our regular user mailbox they type in the wrong address and send it to the internal email address of the contact. When this happens Exchange will automatically forward that email to the primary email address of the contact, which is an external domain.

    We have changed the internal email addresses of the contact to avoid the problem, but in general we would like to block all external senders from sending to our contacts as this could lead to information leakage or possibly even be exploited by malicious users.(?)



    Set-MailContact <contact> -RequireSenderAuthenticationEnabled $true
    • Marked as answer by hanskristian85 Friday, February 23, 2018 11:51 AM
    Friday, February 23, 2018 11:46 AM

All replies

  • Hello everyone,

    For distribution groups you can require that all senders are authenticated, is there any way to configure the same requirement for contacts?

    The scenario is that we have a regular user mailbox and a contact that have very similar names. While the primary address of the contact is external, they also have very similar internal email addresses based on the email address policy.

    When an external 3. party tries to send an email to our regular user mailbox they type in the wrong address and send it to the internal email address of the contact. When this happens Exchange will automatically forward that email to the primary email address of the contact, which is an external domain.

    We have changed the internal email addresses of the contact to avoid the problem, but in general we would like to block all external senders from sending to our contacts as this could lead to information leakage or possibly even be exploited by malicious users.(?)



    Set-MailContact <contact> -RequireSenderAuthenticationEnabled $true
    • Marked as answer by hanskristian85 Friday, February 23, 2018 11:51 AM
    Friday, February 23, 2018 11:46 AM
  • That was a lot easier than expected, I cant belive i didnt find that command.. thanks Andy.
    Friday, February 23, 2018 11:54 AM