domainSigningPrivateKey

Bring Your Own DKIM A private key that's used to generate a DKIM signature. The private key must use 1024 or 2048-bit RSA encryption, and must be encoded using base64 encoding.

NOTE: You have to delete the first and last lines ('-----BEGIN PRIVATE KEY-----' and '-----END PRIVATE KEY-----', respectively) of the generated private key. Additionally, you have to remove the line breaks in the generated private key. The resulting value is a string of characters with no spaces or line breaks.