2.2.4.1.1.2.6.11 EcpUrl-extinstall
The EcpUrl-extinstall element contains a value that, when appended to the value of the EcpUrl element (section 2.2.4.1.1.2.6.9), results in a URL that can be used to view or change the mail add-ins currently installed in the user’s mailbox. It is an optional child element of the Protocol element (section 2.2.4.1.1.2.6).<17>
The value of the EcpUrl-extinstall element is similar to the following: "Extension/InstalledExtensions.slab?exsvurl=1&realm=contoso.com".