A Digital Certificate can be validated by passing it through the public encryption process with the public key for the user to yield the digest. This can be compared with the calculation of the digest from the claimed identity of the user and their public key.
If the two calculations yield the same result then the certificate is valid. Digital certificates are appended to messages to verify the authenticity of the source of the message. A business’s IT should fundamentally let it flourish and not let it down when needed most in times of disaster.