Signs in the local client automatically using the last sign-in name and saved password information. Scriptable.




This method takes no parameters.

Return Value

Returns one of the following values. For managed code applications, these return values are received in the form of a COMException.


Success. See Remarks.


The Sign In dialog box is enabled and visible when this method is called.


The client is already signed in (scripting).


The client is already signed in.


Returned for one of the following reasons:

  • First-time user.

  • No available credentials.

  • Cannot determine local state.

  • Lost connection.

  • Password encoding failed.

  • Unspecified internal error. Cannot access object.

For a table of MSGR_E_* constants, see Error Codes.


This method is used for initial sign-in if necessary, but requires that the sign-in credentials are previously stored by the client user.

To sign in with a name and password other than the defaults, use the IMessenger::Signin method. This method always displays the Sign In dialog box, even with cached credentials. If saving the password locally is not enabled by a specific user option, this method fails.

If this method fails, implementers can display the Sign In dialog box by calling the IMessenger::Signin method with null strings for the sign-in name and password.

Because sign-in relies on server authentication, several possible error conditions are not checked for by the HRESULT of IMessenger::AutoSignin method; instead, they are returned in the IMessenger::Signin method. These error conditions include, but are not limited to, bad credentials stored from the last sign-in attempt, a blank sign-in name or password, and connection problems, each of which is differentiated by the hr parameter of the event. To determine whether the sign-in sequence succeeded, clients should always check both the HRESULT of IMessenger::AutoSignin method and the hr parameter of the IMessenger::Signin event.


The following example creates an int parentHandle and sets it to a zero value. The Signin method of the IMessenger interface requires a null or zero value in the first parameter position with an account name and password in the second and third parameter positions. In this example, the account might not have been supplied by the user so the code tests the string for length to determine which IMessenger interface method to call.

Copy Code
int parentHandle = 0;
if (account == null)
	communicator.Signin(parentHandle, account, passwd);
	connected = true;
   catch (ArgumentException AE)
	 connected = false;
   catch (COMException CE)
	connected = false;



Requires Microsoft DirectX 9.0, C Runtime libraries (msvcm80.dll) on Microsoft Windows© Vista, Microsoft Windows XP Service Pack 1 (SP1) or later, or Microsoft Windows 2000 with Service Pack 4 (SP4). Any Communicator-imposed restrictions apply. .


Requires Microsoft Office Communications Server 2007, AV MCU (for Media Support), Media Relay (for NAT/Firewall traversal) on Microsoft Office Communications Server 2007.


Microsoft Office Communicator 2007 Automation API

IDL file


See Also