How to Manage Senders in Mimecast

Mimecast’s "Manage Senders" feature allows users to control their personal allow/block lists for email filtering. This ensures trusted senders are not marked as spam and unwanted emails are automatically rejected.

📨 What It Does:

When an email is held/quarantined or flagged by Mimecast’s filtering (e.g., for spam or impersonation), you might receive a digest email or visit the Mimecast Personal Portal, where you can:

✅ Allow a sender – future emails from that address or domain bypass filtering

🚫 Block a sender – future emails from that address are automatically rejected

🧰 View/adjust your current allow/block list

🔐 Step 1: Log In to the Mimecast Personal Portal

1. Open your web browser and navigate to: https://login.mimecast.com
2. Log in using your work email address.

📬 Step 2: Navigate to "Manage Senders"

1. From the dashboard, select Advanced (three dots).
2. Select the "Blocked Senders"or "Permitted Senders"section from the menu.
3. You’ll now see a list of all the senders you’ve manually allowed or blocked.

✏️ Step 3: Edit Your Sender Lists

To add a sender:

Click “Add Permitted Sender”or “Add Blocked Sender” (top right)

Enter the email address or domain (e.g., @example.com)

Click Save

To remove a sender:

Click the trash/bin icon next to the entry you want to remove