To block mail from specific domains, create a policy in IMSVA and use the Header keyword expressions as a condition to match the domain.
- Log in to IMSVA web console.
- Go to Policy > Policy List.
- Create a new policy by clicking Add and then select Others.
- Under Step 1: Select Recipients and Senders, assign the values for the following:
- Recipients - <your company's email domain>
For example: test@mycompany.com
- Senders - *@*.domain.com
Ex: *@*.domain.com
- Recipients - <your company's email domain>
- Click Next.
- Under Scanning Conditions, go to the Content section, tick the Header keyword expressions option and click it to configure its setting.
- Under Specific headers match, tick the From checkbox.
- Click Add to create a Keyword Expression.
- On the Match field, select Any specified.
- Click Add and type following keyword expression values:
\w+([\.-]?\w+)*@[\s\S]+\.domain\.com (This can match xxx@xxx.domain.com.)
\w+([\.-]?\w+)*@domain\.com (This can match xxxx@domain.com.) - Click Save
- Save and then select the Header keyword expression. Then click Next.
- Select the action for the rules that you created. For example, Quarantine, Delete entire message, etc.
- Assign a Policy Name and Order Number for your policy. The Order Number indicates the priority of the rule, with 1 being the highest priority.
- Save the new policy.