Digital IDs and Encryption

[lanmanjs]

Kinda long I know but:

I am in the process of setting up encryption between some of my users and
their business partners. I have set this ability up with other partners a
number of times without incident. This time I received a public key from
the partner and was told that in addition to getting and installing Digital
IDs on each station I am to manually install this public key as well. Fine,
did that using 3rd party for ID's instead of KMS from Exch itself!! Sent a
Signed message to partner and got a response back that the ID's were being
stripped. They sent a Signed message to my users anyway even with the
Public Key they had me manually install. We updated their Contacts with
this message - which worked so now we have their cert on our systems. They
sent an encrypted email then and I get a message trying to open it: "Can't
open this item. Your Digital ID name can not be found by the underlying
security system." To test all of this I then set up new ID's with a
different outside address from the problem partner and tested to see if I
would have issues with it and was able to set it all up start to finish with
no problems - worked exactly as it should.
The business partner tells me that the "underlying security system" is my
own Exch box and that it is me causing the problem. Question is, what is my
"underlying security system" and where do I set the properties for it? I
have been through Exch System Mgr backwards and forwards not to mention I
set all of this up without any difficulty using someone else. Am I missing
something or is it really me and not him?

Any assistance would be greatly appreciated.
lanmanjs

 

[idoride]

If you found an answer I would love to hear it. I have had the same issue and I have never figured it out.

Let me know if you have a solution.

Thank you