HTTP Strict Transport Security (HSTS) is a security mechanism used by web servers that instructs clients to connect only using HTTPS. The server adds Strict-Transport-Security to the HTTP response header and this is interpreted by a compatible client.
Encryption Management Server uses Strict Transport Security headers in release 3.4.2 MP2 and above.
However, this can cause enrollment to fail when Encryption Desktop clients attempt to enroll with Encryption Management Server 3.4.2 MP2 and above.
Ensure that the load balancer does not add Strict Transport Security headers.