1. Hold down the Ctrl key, select the emails containing the sender domains you want to block, and then click Kutools > Junk > Block Sender Domains.

2. Then a dialog box pops up informing you which sender domains are blocked, click OK to close it.

3. Go ahead to click Kutools > Junk > Enable Junk Email Filter.

4. In a popping up Kutools for Outlook dialog box, please click the OK button. Then this Junk Email Filter utility is turned on.

Notes:

• The sender domains of the selected emails will be added to the blocked list as rules and you can view and edit these rules in the Junk Email Filter Manager.
• You can also block one or multiple email sender domains by the following steps.
  1. Right click one or multiple selected emails.
  2. Select Junk (Kutools) > Block Sender Domains from the list. See screenshot:
  

Thereafter, when emails from these sender domains arrive, they will be treated as spams and filtered to the Junk folder automatically.

If you have already created block sender domains rules with the above method, this section is going to show you how to manage the existing rules. Please do as follows.

1. Click Kutools > Junk > Rule Manager to open the Junk Email Filter Manager dialog box.

2. In the Junk Email Filter Manager dialog box, double click the Block Domain rule you want to edit to open it.

Tips: You can also click to highlight the Block Domain rule and click the Edit button.

3. Now the Junk Rule Wizard opens, you can change the criteria and sender domains by clicking the underlined text, see screenshot:

4. Now the Text Contains dialog pops out, and you can add new domains, edit existing domains, delete, tick, or untick domains as you need. After finishing your operations, click OK to save the changes.

• Click this button to add new domains. It will open the Search Text dialog. In the Search Text dialog, type a domain into the New Search Text box, click the Add button, and then click the OK button. Then the new domain is added to the Text Contains dialog.
  
• Click this button to edit the currently selected domain.
•   Click this button to remove the currently selected domain.
•   Click this button to select all domains added in the Text Contains dialog.
•   Reversely select the domains in the Text Contains dialog.

5. It returns to the Junk Rule Wizard, and you can see the underlined domains changed based on your modifications. Click Next button to go ahead.

6. In the next Junk Rule Wizard window, set the exceptions you need, if you want to skip this step, please click Next button directly, see screenshot:

7. In the last Junk Rule Wizard window, specify the rule name, rule notes and other options you need, and click Ok button to finish the settings, see screenshot:

8. Then it returns to the Junk Email Filter Manager dialog, remain the Block Domain rule ticked, and click Ok to close the dialog.

Notes:

• Make sure the Junk Email Filter is turned on.
• Click the Enable Junk Email Filter again will turn off the whole Junk feature. If you only want to disable a certain rule, please go to the Junk Email Filter Manager and uncheck the rule.
• Check the Display the rule description inline wrap option, the rule description will display as inline wrap if they are too long to fully display in one line of the window.
• In the Junk Email Filter Manger, click to highlight the Block Domain rule, and you can click the underline text in the Rule description section to edit the rule name, rule notes, and domains directly.
  
• The rules in the Junk Email Manager are executed in the following order:
  The rules will be executed from top to bottom. For example, if an email meets the conditions set in the first rule, it will be immediately moved to the Junk Email folder, then the following rules will not be applied on this email. If the first rule is a never block rule, when an email meets the conditions in this never block rule, it will remain in the Inbox folder even if it meets the conditions in the following block rules.
• If you have checked the Stop processing other rules option for a rule, when an email meets the conditions of that rule, the rules after it will not be executed.
• You can tick or untick the Enable check box to enable or disable all rules in the Junk Email Filter Manager dialog box at the same time.
  
• If you want to copy or delete multiple rules at the same time, hold down the Ctrl key, select the rules one by one, right click the selection and then choose Copy or Delete from the context menu.
  
• If a junk email rule has been created with an empty Rule remark field, a part of the rule’s information will be displayed as a remark in the Remark column.