Introduced in Exchange 2010 SP-2 Update, the way users now log into the Control Panel has changed. When wanting to change permissions for Distribution lists or user permissions, you must log in using the admin@domain.com login and password assigned.
1. You will need to start by navigating to your Control Panel URL (https://my.securembox.com) Followed by logging into your Control Panel with the administrative credentials.
2. Once logged in, on the left select Microsoft Exchange, then in the next panel select Distribution Lists.
3. Highlight your Distribution list, then select Edit Distribution List
4. Once the panel has completely loaded, select Manage Permissions. In the next panel you may add or remove members and their assigned permissions.
5. Once completed, hit the Save button to save your settings.