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Enabling the Edge Security Pack (ESP) may cause STARTTLS connections over SMTP to fail.

Typically, an SMTP service is created as Generic with Server Initiated Protocols set to SMTP. All Traffic received by the LoadMaster is passed through to the Real Server. This includes STARTTLS for SMTP connections.

ESP is available for SMTP services. This allows logging of all SMTP connections.

However, if ESP is enabled, a Generic SMTP service STARTTLS connection will no longer be possible through the service. Normal SMTP will work fine. The reason for this is that ESP needs to terminate the STARTLS connection in order to examine the hostname. 

To allow for this, i.e. an SMTP service with ESP enabled to operate in STARTLS mode - the Service Type must be changed from Generic to STARTTLS protocols.

With ESP enabled, the Permitted Domains field should be set to include the domain name used for SMTP connections.

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