| Possible values | Names | Descriptions |
|---|---|---|
| 1 | AUTH_NONE | No authentication (used internally) |
| 2 | AUTH_ANONYMOUS | ANONYMOUS SASL authentication type. In this case "userName" is used as trace for SMTP server |
| 3 | AUTH_EXTERNAL | EXTERNAL SASL authentication type. In this case "userName" is used as identification token. |
| 4 | AUTH_PLAIN | Authenticate using PLAIN SASL method. Password is sent to server in plain format. |
| 5 | AUTH_LOGIN | Interactive plain authentication (SASL LOGIN) |
| 6 | AUTH_CRAM_MD5 | CRAM-MD5 SASL authentication type |
| 7 | AUTH_CRAM_SHA1 | CRAM-SHA1 SASL authentication type |
| 9 | AUTH_SCRAM_SHA1 | SCRAM-SHA1 SASL authentication type |
| 10 | AUTH_NTLM | NTLM authentication type |
| 15 | AUTH_AUTO | Automatic authentication type. Method will be chosen automatically according to server capabilities (in strongest first order) . |