LTC1872B problem

Has anyone succesfully used the LTC1872B boost converter and have an idea why it would not work? I built a 9 V to 100 V boost circuit that worked but all subsequent attempts to use the device have failed. The IC just does nothing. Pin 1 is above 1/2 volt as required but the output is low so the FET never gets turned on. Linear Technology has no application assistance as far as I can tell and do not reply to emails.

I've had no trouble getting ahold of Linear tech support. Their phone support is good too. As always, write down everything you observed, if a pin is not oscillating as intended know whether it is stuck high or low, etc. Have your protoboard in front of you and if at all possible hooked up with a scope available.