I have a problem.My drawing has a error "insufficient memory to perform operation" when I open excel in drawing cad by OLE object.who can help me solution this problem.

Your drawing does not have a problem but your computer does.  You probably have too little RAM installed and your swap file (virtual memory) is set too low as well.Post your complete system specs.

You can also insert Excel tables as AutoCAD entities (Paste As) - they require less memory.