Tightening online security has become a must-do job due to increasing cybercrimes. Deploy as many layers as possible if you are into online business. Today, we are going to talk about blocking TLD in Microsoft 365. It’s just one of many methods to enhance security. Blocking specific TLDs, such as .com, .org, or .net. in Microsoft 365 – can help prevent spam & phishing attacks. This guide will provide a step-by-step approach to how to block TLDs in Microsoft 365. TLD is short for Top-Level Domains.
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Why Block Top-Level Domains?
You must be wondering why block TLDs, no? Well, here’s the answer: blocking TLDs can significantly reduce the number of unwanted emails – reducing the risk of cyberattacks. Certain TLDs are notorious for being used by malicious actors to send harmful content. You can reduce the risk of security breaches and protect sensitive information if you identify and block these TLDs.
How to Block Top-Level Domain (TLD) in Microsoft 365? | A Step-by-Step Guide
Step 1: Access the Exchange Admin Center
Access the Exchange Admin Center (EAC) in Microsoft 365 to start the process. The EAC is where you manage mail flow rules where specific TLDs can be blocked. Check steps:
Sign in to Microsoft 365 Admin Center
Go to the Microsoft 365 Admin Center and sign in with your admin credentials.
Navigate to the Exchange Admin Center
Check the screen’s left side and select “Exchange” from “Admin centers” to open the EAC.
Step 2: Create a New Mail Flow Rule
Mail flow rules allow you to apply specific actions to emails based on various conditions. You must create a rule that identifies emails from the specified TLDs and blocks them.
Go to Mail Flow
In the EAC, select “Mail flow” from the left-hand menu.
Create a New Rule
Click the “+” icon and select “Create a new rule.”
Step 3: Configure the Rule Conditions
It’s time to define the conditions that the rule will apply to. In this case, you will set conditions to identify incoming emails from particular TLDs.
Name the Rule
Give your rule a name, such as “Block Specific TLDs.”
Set Conditions
Click on “Apply this rule if…” and select “The sender’s domain is…”
Specify TLDs
Enter the TLDs you want to block, such as “.ru,” “.xyz,” or “.info.” You can add multiple TLDs by separating them with a semicolon.
Step 4: Define the Action
Now that the rule is set to identify emails from the specified TLDs, you need to define what action to take. The most common action is to reject the message.
Select an Action
Select “Do the following…” and open “Reject the message with the explanation.”
Customize the Explanation
Enter a message that will be sent to the sender when their email is rejected, such as “Emails from this domain are not accepted.” Or, it could be anything you want.
Step 5: Set Exceptions (If any)
Sometimes, you want to allow emails from one or more senders within the blocked TLDs. You can set exceptions to your rule to permit these emails.
Add Exceptions
Click on “Except if…” and define the conditions for exceptions. For example, you can allow emails from specific addresses or domains within the blocked TLDs.
Step 6: Save & Activate the Rule
After configuring the conditions, actions, and exceptions – it’s time to save & activate the rule.
Save the Rule
Click “Save” to create the rule.
Activate the Rule
Ensure the rule is enabled by checking the status in the list of mail flow rules.
Step 7: Test the Rule
You must test the rule to ensure it’s working as intended. Send test emails from the blocked TLDs and verify that they are rejected with the specified explanation.
Send Test Emails
Use email addresses with the blocked TLDs to send test emails to your organization.
Verify Rejections
Check that these emails are rejected and that the sender receives the rejection message.
Monitoring & Maintenance
Blocking TLDs is not a one-time task. Regular monitoring is essential for your email security.
Review Logs
Regularly review email logs to identify any unusual patterns or missed threats.
Update Rules
As new TLDs become problematic, update your rules to include them.
Check Exceptions
Periodically review exceptions to ensure they are still necessary and do not pose security risks.
Best Practices for Managing Mail Flow Rules
To maintain a robust email security posture, consider the following best practices:
Keep Rules Simple
Avoid overly complex rules that are difficult to manage.
Document Changes
Keep noting any changes to your mail flow rules for future reference.
Stay Informed
Keep up-to-date with the latest email security threats and trends to adjust your rules accordingly.
Conclusion
Blocking specific TLDs in Microsoft 365 is a powerful way to enhance your email security. Follow these steps to effectively block unwanted emails from malicious TLDs. This will reduce the risk of spam & phishing attacks. Monitor your mail flow regularly for security certainty.
Do you need any help with email security?
Connect with us (Leasepacket) – we offer all kinds of security & server solutions and expert support. Contact us to get a quote!
FAQs
Q1. How do I access the Exchange Admin Center in Microsoft 365?
Sign in to the Microsoft 365 Admin Center, go to “Admin Centers,” and then select “Exchange” to open the Exchange Admin Center.
Q2. Can I block multiple TLDs at once in Microsoft 365?
Yes! You can block multiple TLDs by separating them with a semicolon while selecting TLDs in the rule conditions.
Q3. What happens to emails from blocked TLDs?
Emails from blocked TLDs will be rejected, and the sender will receive a rejection message that you put in.
Q4. Is it possible to allow some emails from blocked TLDs?
Why not! You can set exceptions to allow emails from specific addresses or domains within the blocked TLDs.
Q5. How can I test if my rule for blocking TLDs is working?
Send test emails from addresses with the blocked TLDs to your organization and verify that they are rejected with the specified explanation.
Q6. Why is it important to regularly update & monitor mail flow rules?
Regular updates & monitoring ensure your email security remains effective against new threats and that no legitimate emails are blocked unnecessarily.
Q7. What if I need help with my email security?
You can connect with Leasepacket. Leasepacket offers all kinds of security & server solutions and expert support. Contact us to get a quote!