Internet Explorer performs a number of safety checks before initializing an ActiveX control. It will not initialize a control if the kill bit for the control is set in the registry, or if the security settings for the zone in which the control is located do not allow it to be initialized.
This functionality can be controlled separately for instances of Internet Explorer spawned by Office applications (for example, if a user clicks a link in an Office document or selects a menu option that loads a web page). A security risk could occur if potentially dangerous controls are allowed to load.
Set the policy value for Computer Configuration -> Administrative Templates -> Microsoft Office 2013 (Machine) -> Security Settings -> IE Security 'Bind to Object' to 'Enabled' and place a check in the 'outlook.exe' check box.
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: System and Communications Protection.This control applies to the following type of system Windows.