Check the line
' Old school tip ': When you've finished a conference call hang up. Then pick the line up again and check for the dial tone. Chances are there are as many different conference phones as there are conference rooms you'll see in a consulting career, and the only way to know the line is dead is to hear the dial tone of a clean line... think about what the first thing you say after a conference call is; then think about whether you'd want the other people who were on the call to hear it? From icanhascheezburger .