sounds like some assembly files are corrupt, consider to use the following tool to detect failed assembly binds.Assembly Binding Log Viewer (Fuslogvw.exe)
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cptools/html/cpgrffusionlogviewerfuslogvwexe.asp
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cptools/html/cpgrffusionlogviewerfuslogvwexe.asp
应该不是程序集绑定错误,因为所有地方vbgrid都能显示出来表示程序集能被正确定位,用fuslogvw也没发现问题。