Why you might want to see file extensions
File extensions are the letters after the dot in a filename — like .exe, .pdf, or .txt. Windows 11 hides them by default, which can make it harder to spot when a file is not what it claims to be. A file named "document.pdf.exe" looks like "document.pdf" when extensions are hidden, but it is actually a program that could be malicious.
Showing extensions helps you stay safer when downloading files, especially from email or unfamiliar websites. It also makes it easier to organize your files and understand what each one actually is. Once you turn this setting on, you will see the true type of every file on your computer before you open it.
Key Takeaways
- Windows 11 hides file extensions by default, which can hide the true type of a file and create a security risk when malware uses double extensions to disguise itself.
- You can turn on extensions in File Explorer by opening the View menu and checking the "File name extensions" box.
- Once you turn on extensions, they will stay visible for all files and folders on your computer and the setting does not change how files open or work.
- Seeing extensions helps you spot suspicious files before you open them, especially files that claim to be documents but end in .exe, .scr, .bat, or .msi.
- This is a display-only change — turning extensions on does not affect your files, programs, or how your computer runs.
How to show extensions in File Explorer
Open File Explorer by pressing Windows key + E, or by clicking the folder icon on your taskbar. You can navigate to any folder — the setting works the same way everywhere.
Look at the top of the File Explorer window for the View tab in the ribbon menu. Click it to open the View options. On the right side of the ribbon, you will see a checkbox labeled "File name extensions". Click the checkbox to turn it on.
File extensions will now appear on every file in File Explorer when ready. This setting stays on across your entire computer — you do not have to turn it on again for each folder or each time you open File Explorer. Once it is enabled, you will see the full filename for every file you look at, whether it is on your desktop, in your Documents folder, in Downloads, or anywhere else.
What extensions tell you about a file
Common safe extensions include .pdf (document), .jpg or .png (image), .docx (Word document), .xlsx (spreadsheet), and .txt (text file). These are the file types you expect to see when someone sends you a document or image.
Extensions that should raise a red flag include .exe (program), .scr (screensaver), .bat (batch file), .cmd (command file), .msi (installer), .vbs (script), and .com (executable). If someone sends you a file claiming it is a photo or document but it ends in one of these, do not open it — it is a program, not what the filename suggests.
Double extensions like "resume.pdf.exe" are a common trick used by malware. The file is actually an executable program, but the .pdf in the middle makes it look harmless. With extensions hidden, you would only see "resume.pdf" and might open it without thinking. With extensions visible, you when ready see that it is an .exe file and can avoid the danger.
What happens after you turn extensions on
Once extensions are visible, you will see them on every file you look at in File Explorer. This includes files on your desktop, in your Documents folder, in Downloads, in your Pictures folder, and anywhere else on your computer where you browse files.
Turning on extensions does not change how files work or how you open them. Double-clicking a .docx file still opens it in Word. Double-clicking a .jpg still opens it in your image viewer. Right-clicking a file and choosing "Open with" still works the same way. The only difference is that you now know what type of file you are about to open before you click it.
If you ever want to hide extensions again, go back to File Explorer, click the View tab, and uncheck "File name extensions". The extensions will disappear when ready, though the setting is straightforward to turn back on if you change your mind.
Why Windows hides extensions by default
Microsoft hides extensions to make Windows look simpler for casual users. The theory is that most people do not need to see them and the interface looks cleaner without them. In practice, this design choice makes it easier for malware to disguise itself as something harmless.
Security researchers recommend turning extensions on for this reason. The small amount of extra text on your screen is worth the protection it gives you against files that are not what they claim to be. It is one of the easiest changes you can make to reduce the risk of opening a malicious file by accident.
How to spot suspicious files once extensions are visible
When you read a file or receive one in email, take a moment to look at the extension before you open it. If someone claims they are sending you a photo but the file ends in .exe or .scr, that is a warning sign. If a file has two extensions like .pdf.exe, that is almost always malicious.
If you see a file with an extension you do not recognize, search the extension online — for example, search ".scr file" or ".vbs file" — to find out what it is. If it is a program or script file and you did not expect to receive it, do not open it. If you are unsure, ask the person who sent it to you what the file is for, or ask them to resend it in a different format.
Frequently Asked Questions
Will turning on extensions break anything or change how my files work?
No. Turning on extensions only changes what you see in File Explorer. It does not change how files open, how programs run, or anything else about how your computer works. It is purely a display setting.
Can I hide extensions again if I change my mind?
Yes. Go back to File Explorer, click the View tab, and uncheck "File name extensions". Extensions will be hidden again when ready. You can turn them back on the same way whenever you want.
What if I see a file with an extension I do not recognize?
Search the extension online — for example, search ".scr file" or ".vbs file" — to find out what it is. If it is a program or script file and you did not expect to receive it, do not open it. If you are unsure, ask the person who sent it to you what the file is for.
Does showing extensions protect me from all malware?
No, but it is one layer of protection. Seeing extensions helps you spot obvious tricks, but malware can still come in legitimate-looking files. Extensions are part of staying safe, not a complete solution on their own.
Why do some files still not show an extension even after I turn this on?
Some system files and certain file types are hidden by Windows even when extensions are turned on. This is normal. The setting works for the files you read and receive, which is where the security benefit matters most.