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Notifies the provider that it is joining a synchronization session.
HRESULT BeginSession( SYNC_PROVIDER_ROLE role, ISyncSessionState * pSessionState);
[in] The role of this provider, relative to the other provider in the session.
[in] The current status of the corresponding session.
S_OK
Provider-determined error codes
The provider must return an error if it cannot begin a session. This can occur when the provider has not been initialized, has an invalid configuration, or is already enlisted in an active session.