# IRPCExtensionAuthentications.LoginWithExtensionAuthentication

Location: [gRPC API](https://developer.m-files.com/APIs/gRPC-API/index.md) > [Vault API](https://developer.m-files.com/APIs/gRPC-API/vault/index.md) > [Extension authentications](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/index.md)

HTML version: https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/LoginWithExtensionAuthentication/

Badges: `Vault API / standard` `write` `session` `returns metadata structure version`

Logs the caller in to an external system with encrypted credentials. Used by M-Files clients
that encrypt the credentials above the transport layer; applications should call
[StoreExtensionAuthenticationCredentials](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/StoreExtensionAuthenticationCredentials/index.md)
over TLS instead.

- **Service:** [Extension authentications](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/index.md) `MFiles.IRPCExtensionAuthentications`
- **gRPC method:** `/MFiles.IRPCExtensionAuthentications/LoginWithExtensionAuthentication`
- **HTTP (mf-http-grpc):** `POST /grpc/v1/login-with-extension-authentication`
- **Request:** [`LoginWithExtensionAuthenticationRequest`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/LoginWithExtensionAuthentication/index.md#request)
- **Response:** [`LoginWithExtensionAuthenticationResponse`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/LoginWithExtensionAuthentication/index.md#response)
- **Book and level:** Vault API, standard
- **Kind:** write
- **Session:** Required: the session ID from LogIn in the mfiles-session-id-bin metadata.
- **Idempotent:** no
- **Returns metadata structure version:** yes (in the mfiles-metadata-version-bin trailer)
- **Streaming:** none (unary)

<a id="remarks"></a>

## Remarks

- Data that the server cannot decrypt fails with "The parameter is incorrect.".

<a id="request"></a>

## Request: LoginWithExtensionAuthenticationRequest

> Nested message fields are expanded to depth 3; follow a type link for deeper levels and for the type's own page.

| Field | Type | Description |
|---|---|---|
| `target` | `string` | The `id` of the target. |
| `ear_data_encrypted` | `bytes` | The credentials, encrypted with the server's public key in a format internal to the M-Files clients. |

<a id="response"></a>

## Response: LoginWithExtensionAuthenticationResponse

No fields.

<a id="related"></a>

## Related methods

- [StoreExtensionAuthenticationCredentials](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCExtensionAuthentications/StoreExtensionAuthenticationCredentials/index.md): Logs the caller in to an external system by storing the caller's credentials for it.