Error when trying to obtain a certificate: The specified item could not be found in the keychain

Question

I was having a problem with codesigning my apps, so I deleted all the keys from the keychain. Then I went to Certificate Assistant => Request a certificate from a Certif

Answer 1

Keychain Access will not let you Request a Certificate from a Certificate Authority With "identity"... unless you have both the private key and public key for identity in your keychain. I ran into this when I only had the private key and not the corresponding public key.

You can create the public key from the private key and import it into your keychain using the procedure described in I lost my public key. Can I recover it from a private key?

Once I imported the public key I was able to use the Request a Certificate from a Certificate Authority With "identity"... command without triggering the The specified item could not be found in the keychain error.