Under the Data Loss Prevention > DLP Policies:

• Enable transport Data Loss Prevention is checked
• Sub-option Apply policies to "All messages" is selected

1. On the left column, go to Administrations > Special Groups.
2. Click the Add button to create a special group.

   

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3. On the Add Special Group window, perform the following:
   1. Enter a name for the new group.
   2. On the Select Accounts section, choose the Enter SMTP Address option.
   3. Add the internal domain for the DLP exclusion.
   4. Click the Add button to add the internal domain.
   5. Click Save.

   

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4. The created group should be listed on the Special Groups section afterwards.

   

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1. Go to Data Loss Prevention > DLP Policies, and make sure that the Prerequisites are set.
2. Click the name of the DLP policy to be edited (in this example, "TestPolicy"), then do the following:
   1. On the Accounts dropdown, choose Specific recipient(s).
   2. Click the Edit link on the Selected Recipients section.

   

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3. Choose Anyone under the Select Accounts window.

   

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4. Expand Exclude Accounts section, then perform the steps below:
   1. On the dropdown, select the Browse from special groups option.
   2. Select the group containing the internal domain created in Section A.
   3. Click the Add button to add the group.
   4. Click Save.

   

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5. Confirm the Recipient(s) list, click Save.

   

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6. Click Save to apply the new settings.

   

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