Macros Explained: Why Microsoft Office Files Can Be Dangerous
 

Microsoft Office documents containing built-in macros can be dangerous. Macros are essentially bits of computer code, and historically they’ve been vehicles for malware. Luckily, modern versions of Office contain security features that will protect you from macros.

Macros are still potentially dangerous. But, like a lion at the zoo, you’d have to go out of your way to be hurt by them. As long as you don’t bypass the built-in security features, you shouldn’t have to worry.
What’s a Macro?

Microsoft Office documents — Word, Excel, PowerPoint, and other types of documents — can contain embedded code written in a programming language known as Visual Basic for Applications (VBA).

You can record your own macros using the built-in Macro Recorder. This allows you to automate repetitive tasks — in the future, you’ll be able to repeat the actions you recorded by running the macro. Follow our guide to creating Excel macros for more information. Macros you’ve created yourself are fine and don’t pose a security risk.

However, malicious people could write VBA code to create macros that do harmful things. They could then embed these macros in Office documents and distribute them online.

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