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I want the ability to lookup an encryption certificate for SMIME in Outlook for recipients who have SMIME certs, but I just don't have their public key.

I noticed the keychain has a directory feature. Can I use this to add a compatible directory to lookup their public key for SMIME encryption?

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According to the Apple TS article "Using Keychain Access to search directory services for certificates", if your Mac

  • is configured to use a directory service,

  • has the CA signing certificate trusted in either your login or the system keychains,

  • has a valid signed user certificate with the appropriate attributes,

then Keychain Access can be configured (Preferences → General → Search directory services for certificates) to search for certificates on the configured directory service. will also automatically search for certificates as well.

Unfortunately, I haven't done this personally, so I can't vouch for how well it works or have any advice on any issues. This reads to me like a feature designed to be used with a centrally-managed IT infrastructure with directory and certificate services. It does not sound like it is designed to work outside that sort of environment.

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Not sure if this would help, but yes, you can create and retrieve certificates to save in your keychain.

enter image description here

You might also try this system:

Retrieved a free certificate from COMODO

Please ensure, that you always select "United States" as you country of residence. Otherwise, you will not get a proper private key embedded into you certificate.

Alternatively, you can look up the public key: Using WWW or email methods.

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If your question were about PGP, then the answer would be you could download the recipient's public key from , for example.

But as for S/MIME, the keystores are scattered.

It is weird, since it is straight-forward to publish 1 your S/MIME certificate .

But the idea does not seem to have taken off. Case in point, here 2 is an announcement from 6/2/2011 , about 3, which today (2014), seems to have 140 users.


1 Sharing SMIME certs

2 from google groups


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