Yes, i found to lost some preferences, but after i add it, all the command button lost in my project. the error message in the log file as:
Line 57: Class FlatButton.XFlatButton of control cmdSearch was not a loaded control class.

I noticed the 'XFlatbutton' which i used for my command button did not selected in the project component and also it does not allowed me to add in. The message prompted me:
'Name conflicts with existing module, project, or object library' when i select the component.