Messaging Gateway

When I client who uses Mimecast emails us, and mimecast uses opportunistic TLS, SMG rejects the messages with a retry later.

The message header contains a failed TLS negotiation

Unable to initiate TLS - Possible CA Problem - sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

INFO |0716-101804 070|...|||Error Code|21040|Socket closed

The SMG is running the latest updates 10.5.2

We can email the client fine. Anyeon else expercing issues wiht this or similar  ?

Why is SMG not falling bakc to clear if TLS negotiation fails. Why is TLS failing ?

thank you in advance

I will answer my own question in the absence of any other response (as seems common on this forum)

The bottom line is TLS is broken in SMG. It cannot cope with strict enforcement, I needed Mimecast to make an exception and relax the TLS to our domain

The bugs and issues in this product is quite frankly staggering, giving we are supposed to be on version 10

See here

https://support.symantec.com/en_US/article.TECH228576.html

And here for more info on the TLS situation in SMG

http://www.symantec.com/connect/articles/symantec-messaging-gateway-and-tls-post-poodle-internet

What I find most frustrating is that , Mimecast can get the implementation right and handle this well, yet SMG can not.