The data could not be loaded

I have spent one half a day to solve this issue which I get the "the data could not be loaded"error when I click the callback control of compontart.I am puzzled that the error occurs sometimes,not all the time,so i can not find the exactly reason which caused it.I search from internet some people has this problem.but so far,i think there is not a effective method to solve this.Some one said it due to the encode,some one said it due to network security and some said it due to CA bug.Pls give me some help ASAP.I have spent one half a day to solve this issue