When talking about cybersecurity, it is usually emphasized that what fails many times is not so much technology, as antivirus solutions, but The human factor. That is why cybercounts put so much emphasis on the tactics of social engineering To convince a potential victim to end up clicking where you should not or enter credentials without verifying if a website is really what it claims to be. The good thing about this is that preventing it, using common sense, experience and prudence, is in the user’s hand. The bad is when the software plays against that common sense, something that Windows makes in a certain aspect for 30 years.
It was with Windows 95a groundbreaking operating system at the time, when Microsoft began to hide by default the file extensions that allow to identify what type are. For example, the .txt that follows the name of a text file created with the notes, the .PPTX of a PowerPoint, the .docx of Word or the .pdf that completes, you guessed, that of a PDF file.
In this way, the information that the user has at the first glance is the name of the file and the icon that corresponds to it, but nothing else. This is a form of Simplify experience for less expert usersbut also represents an important Security hole By sparing the information provided.
Why it is necessary to know file extensions in Windows
One of the usual ways of distributing malware is making it go through a legitimate file. PowerPoint, Word, PDF … whatever. In these cases, cybercriminals add the ‘supposed’ extension of the file in the name (for example, ‘Fine.pdf’ notification ‘), which Windows will show since it is part of the name and is not the real extension, helping the user to be cheated on the nature of the file.
If Windows showed the extension by default, then it could appear as ‘Fine notification.pdf.exe’being .exe the extension of the Executable files in Windows. That is, a clear clue that it is not, in this case, a document but a program that It starts by double clicking on it, thus activating the malware. Yes, it is an old trick, but that continues to work for cybercounts of wonder.
How to see default file extensions in Windows
Microsoft allows you to change this default behavior of its operating system, so that all the files you see on the desktop and folders They will be accompanied by its corresponding extension and you can meet it at the first glance. You have to follow these steps, both in Windows 11 as in Windows 10that in 2025, ten years after its launch, it remains The Microsoft operating system with the highest market share:
- Open the File explorer.
- Click the tab View at the top if you use Windows 10.
- In Windows 11click on the menu Seealso at the top.
- In Windows 10in the menu that unfolds, activates the box File name extensions.
- In Windows 11select Show In the drop -down menu and then click File name extensions.