Importing User Directories

You can import LDAP Data Interchange Format (LDIF) or comma-separated values (CSV) files into Hosted Email Security. This helps Hosted Email Security to better filter and process messages for valid email addresses. Messages to invalid email addresses will be rejected.


Before you import an LDIF or CSV directory file, note the following:

  • Hosted Email Security only recognizes ANSI-encoded LDIF (with the extension .ldf) and ANSI or UTF-8-encoded CSV (with the extension .csv) files. Do not include blank lines or other irrelevant data in the file that you import. Use caution when creating a file.

  • When importing user directory files, Hosted Email Security replaces all records for a managed domain at once. If any email addresses for a managed domain are imported, all other email addresses for that domain are removed. Newly imported email addresses for that domain, and records for other managed domains, will be kept. If you import an updated user directory file that does not have any information for one of your domains, the entries for those domains remain the same and are not overwritten.

    Every time you import a directory file, it overwrites the old version. If you import an updated directory file that has information for one of your domains, all entries for those domains are overwritten. Use caution when importing a directory.

  • You can only see the directories that are associated with your administrator account. If you are sharing your Hosted Email Security service with another administrator (for example, a value-added reseller) who logs on with his/her specific account information, Hosted Email Security will not show the directories for that account.

  • Every time you add more users to your network, you must import your updated user directories; otherwise, Hosted Email Security will reject email from newly added users.


Trend Micro strongly suggests that you do not import more than 24 directories in a day. Doing so could overwhelm system resources.

  1. Next to Format, select the format type:
    • LDIF

    • CSV


      If you create a CSV file, divide the records into fields for email_address and Firstname Lastname and separate them using a comma and optional quotation marks. Use of spaces or other delimiters is not supported. Use one record per line.

      For example:

      Valid,Bob Smith,Sally Jones
      "","Bob Smith"
      "","Sally Jones"

      Not Valid,Bob Smith,,Sally Jones

      Microsoft Excel will save a two column chart as a CSV using valid formatting.

  2. Next to Name, type a descriptive name for the file.
  3. Next to File location, type the file directory path and filename or click Choose File and select the .ldf or .csv file on your computer.
  4. Click Verify File to read the file and show a summary of how many email addresses were found.

    After the progress bar completes, a summary screen appears showing the following:

    • Summary: A summary of the information above

    • Domains and Number of Current Users to Replace Current Users: The domains that you specified when you subscribed to the Hosted Email Security service

    • Invalid domains: Any domains that are included in your directory file, but are not officially registered with your Hosted Email Security service


      Hosted Email Security does not provide service for these domains and their corresponding email addresses.

  5. Click Import.

    This will import and then enable the email address list.


    You can verify which email addresses were found by selecting your domain name and clicking the Export to CSV button.

    If you need to disable the feature, you can click the toggle.

    The toggle button shows the current enabled or disabled status of Recipient Filter in Inbound Protection > Recipient Filter.