Actually I am trying to activate the macros in my PC. But the Macro setting option is not allowing me to do that as it turned grey and is inactive I can not click on any option. Can anyone please help me to activate the macros?

Try opening or saving the file in question as a .xlsm file. Excel 2007 introduced macros by file type.

If your doc is a .xlsx file, it will never have/allow macros.