Meeting could not be started error message

When I try to start a presentation (using the "Presentation" button) I get the following error message:

The meeting could not be established.  Either there is an incoming remote control session or you ar ehosting a meeting.

Neither of which are correct as far as I am aware - so I don't know why I can't start a presentation.  Is there a way to verify the 2 above things that it says are stopping the meeting starting?

Thanks,

David