>When I want build Project it show an error " UNABLE TO FIND UNKNOWN X " If I ignore this error, project build successfully and the same error accure when I build EXE. There is no error at run time. I search its menu file this 'X' is exist but not found. Please help me how I can found where this error is.
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Ahsan,

Did you check the Project error log which can be accessed from Project menu -> Errors? Also, you can start VFP debugger before build so build log will be output to the Debugger Output window which you can analyze afterwards.