A macro is a series of command or function to automate task in Mirosoft Excel application. It's command run based Microsoft Visual basic module to automate the task such as calculation, copy, etc in Microsoft Excel. Basically it makes the users life easier especially when handling massive amount of data.
On the other hands, due to its nature of programmable function the Macro can be exploited using malicious programs like Viruses, Trojans, Spyware to hijack the operating system via the Microsoft Office Excel application. That is why by default setting the Macro is usually disabled.
However at times it maybe needed especially when opening excel files that requires macro to run it. Otherwise the documents will be open prematurely or error occurs due to disabled Macro.
How to enable/disable macro in Microsoft Office Excel 2007:
Step 1: Click on Office Button → Excel Options
Step 2: Click on Trust Center → Trust Center Settings
Step 3: Macro Settings → Now you have the options to disable/enable the macro. Done!!