Step 1: Login to Cloudmail control panel using the below URL
Step 2: Choose the ‘Blacklist’ option under ‘Domains’ section of Cloud Office control panel
Step 3: Add domain name, email ID or IP address that you wish to blacklist and click ‘Add’
Step 4: Now click on ‘Save’ button to save the changes made.
Step 5: Emails send from the blacklisted domains will be rejected automatically.
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