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Summary: Exchange Server is favored by businesses for secure email communication. Its Data Loss Prevention (DLP) feature ensures compliance and data protection with customizable rules, exceptions, and actions. Testing and activation procedures are outlined. However, the article also mentions the potential for malicious emails, recommending Kernel for Exchange Server Recovery as a solution for database corruption.

Exchange Server stands out as the preferred choice for numerous businesses seeking a reliable professional email server. Apart from offering robust enterprise-level email services, Exchange Server boasts a critical feature known as Data Loss Prevention (DLP), elevating it to a secure and trustworthy platform for confidential email communications. In an era where safeguarding sensitive data is paramount, organizations place a premium on preventing inadvertent leaks through email correspondence, and Exchange Server excels in addressing this concern through its advanced Data Loss Prevention techniques.

The Data Loss Prevention (DLP) feature plays a pivotal role in ensuring compliance with regulatory agency data requirements. DLP comprises a comprehensive set of mail flow rules, each equipped with specific conditions, exceptions, and actions. These rules meticulously scrutinize both emails and their attachments, evaluating their content to safeguard against data breaches and non-compliance.

DLP mail flow rules operate on messages in transit in various ways. For instance, a single rule can inspect incoming message attachments, while another rule can scan for specific text patterns using regular expressions. Furthermore, you have the flexibility to create rules that monitor messages for compliance with your organization’s messaging policies.

Mail Flow Rule Components

Any DLP rule that you want to create will have the following types of components-

  1. Conditions: Conditions are the criteria upon which you intend to evaluate the message. These conditions can examine various aspects of the message, including header fields such as “To,” “From,” “Cc,” and “Bcc.” Alternatively, they can inspect properties such as email text, attachments, subject, size, and classification. To evaluate these conditions, you’ll need a comparison operator, such as “equals,” “does not equal,” or “contains.” If exceptions are not applied to the rule, it will affect all email messages.
  2. Exceptions: Exceptions are utilized for messages where you wish to deviate from a predefined rule. The same comparison operators employed in your conditional rules can also be employed within exceptions. An exception will take precedence over the established mail rule conditions and will bypass messages that meet the exception criteria.
  3. Actions: Actions encompass a range of activities that dictate the course of action taken in response to messages falling within specified conditions. These actions offer diverse functionalities, including rejection, deletion, message redirection, adding extra recipients, appending new prefixes to the subject, and even inserting disclaimers into the message body.
  4. Properties: Properties encompass rule settings distinct from previously applied conditions. They neither constitute exceptions nor actions but rather pertain to aspects such as the timing of condition application and the duration of its validity.
Create a Data Loss Prevention rule

Before enabling a data loss prevention rule created by the user, it’s crucial to conduct thorough testing. This practice safeguards against unintended interactions with messages that could result in data deletion.

  • Create the Rule in test mode: When you create a Rule in test mode, it exclusively focuses on matching email messages with the specified conditions, bypassing the execution of any associated actions. In this mode, you will receive email notifications whenever a message is evaluated against the Rule. Please refer to the following instructions for guidance.
    1. Login to Exchange Admin Center and choose Mail Flow>>Rules.
    2. Either you can create a new rule or edit an existing Rule.
    3. Go to scroll down ‘Choose a mode for this’ and select either ‘Test without Policy Tips‘ or ‘Test with Policy Tips.’
      Test without Policy Tips: This mode will provide the incident report action information applied to the message that matched the conditions.
      Test with Policy Tips: This mode works solely for the Data Loss Prevention feature. It will provide an email related to a matching email message but will not take action.
    4. Click ‘Add action,’ and if the option is not there, click More Options>>Add action.
    5. Click ‘Generate incident report and send it to‘ and select the user to get the emails.
    6. Choose ‘Include message properties‘ and apply such properties that you want to use on the Rule.
    7. Click Save, and a new rule is created.
  • Test whether the new Rule is working correctly: To evaluate the Rule’s effectiveness, you can conduct a series of tests by sending multiple test messages from a different email address to determine if the Rule correctly processes them and delivers the desired information. It is advisable to send a variety of messages that both adhere to and deviate from the Rule’s criteria. These messages should encompass both internal and external sources to ensure comprehensive testing.
  • Activate the well-tested Rule: When you have tested the Rule, you can activate it and enforce it on email communication.

    1. Click Mail Flow>>Rules>>Edit.
    2. Click Enforce, and if you have created an incident report, then Remove it.
    3. Click Save.


The effectiveness of the Database Loss Prevention feature in safeguarding email communications hinges significantly upon the Administrator’s ability to craft a robust rule for data protection. While this mechanism greatly enhances security, it is essential to acknowledge that there remains a potential for malicious emails to circumvent these rules, leading to the potential corruption of the Exchange database.

In the unfortunate event of database corruption, our reliable solution, Kernel for Exchange Server Recovery software, stands ready to assist you in addressing this critical situation. This tool seamlessly scans the EDB file, proficiently recovering all mailboxes within. Following successful recovery, users are empowered to save the retrieved data in various formats or directly restore it to a live Exchange environment, ensuring data integrity and business continuity.

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