Sample name: CallTransferBasic

Sample location: %ProgramFiles%\Microsoft Office Communications Server 2007 R2\UCMA SDK 2.0\UCMACore\Sample Applications\Collaboration\QuickStarts\CallTransferBasic


The application listens for an incoming audio/video call. When one is received, the application accepts the call, and then transfers the inbound call to a third entity. After the transfer begins, the call is disconnected, regardless of the success or failure of the far leg. The user has the option (by changing one of the variables declared at the top of the code) of making an attended transfer or an unattended transfer. An unattended transfer begins the transfer (sends the REFER to the far end) and ends the call on receipt of the transfer request response (202-Reply to the caller). An attended transfer waits to end the call until the subsequent call either succeeds or fails.

The application prints log results to the console, and then exits, performing normal platform shutdown.

The application runs indefinitely in an idle state until it is called.


  • Call transfer, and established call activities

  • Basic call placement

  • Basic incoming audio/video call use

  • AudioVideoFlowhandling and control


  • Microsoft Office Communications Server 2007 R2.

  • Two users capable of sending and receiving audio calls.

  • The credentials for each user, and a client capable of signing in to Office Communications Server.

  • A client signed in to Office Communications Server.

Running the Sample

  1. Replace the credentials in the variables at the beginning of the code sample with the credentials and server of the users from your Office Communications Server topology.

  2. Substitute the address of the called user in the code sample with the address of a valid, currently signed-in user capable of receiving audio calls.

  3. Open the project in Microsoft Visual Studio, and then press F5.

  4. Send a voice call to the user whose credentials the endpoint is using.