Turns off a client-side encryption key pair. The authenticated user can no longer use the key pair to decrypt incoming CSE message texts or sign outgoing CSE mail. To regain access, use the EnableCseKeyPair to turn on the key pair. After 30 days, you can permanently delete the key pair by using the ObliterateCseKeyPair method. For administrators managing identities and keypairs for users in their organization, requests require authorization with a service account that has domain-wide delegation authority to impersonate users with the https://www.googleapis.com/auth/gmail.settings.basic scope. For users managing their own identities and keypairs, requests require hardware key encryption turned on and configured.