The developer's functions of excel and VBA are disabled by default. They can be unlocked using Start->Excel Options window. Check "Show developers tab in the Ribbon" in Popular section. After clicking OK the developers tab is shown at the last place in the ribbon.
Another important thing is the saving xls documetns with recorded macros or inlcuded VBA scripts. You must save the file by Save As dialog box as an Excel Macro-Enabled Workbook with extension .xlsm .