I'm sorry for your troubles while using TeamPulse.
Could you please give us some more details about the problem? Could you send us a screenshot while you reproduce the error? Also which report do you use and with which settings of the filters? Do you have a lot of information for the selected Iteration? Could you try to reduce the scope?
You could also send us your log files, they are usually located here: "C:\Program Files (x86)\Telerik\TeamPulse\Logs"
I'm looking forward for your answer.