The Inner Exception part of the error message shows you have an 'Object reference not set to an instance of an object' error. This may be caused by a calculation that is running that is not handling nulls correctly.
You can use article http://community.landesk.com/support/docs/DOC-6413 to turn on calculation logging to help work out which calculation is returning the object reference error and article http://community.landesk.com/support/docs/DOC-26226 should help you correct the calculation by handling nulls correctly.
Regards,
Martyn