Try running the Check Geometry tool on the File Geodatabase feature class. If there are errors, make a copy of the feature class and then run the Repair Geometry tool.
Thanks Jake and Asrujit for the help. It works fine[ATTACH=CONFIG]31987[/ATTACH], [ATTACH=CONFIG]31988[/ATTACH], [ATTACH=CONFIG]31989[/ATTACH], [ATTACH=CONFIG]31990[/ATTACH]
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Jamal Numan
Geomolg Geoportal for Spatial Information
Ramallah, West Bank, Palestine