How to display file extension

in Windows 7 In Windows 7, when you open Explorer to view the format of a file or document, you can't see it by default, as shown below:

So if Is the file downloaded from the Internet, if you can not see its format, it is easy to double-click this file to cause poisoning or hacking Trojans, so we will introduce how to set up in Windows7 To view the file extension:
1. First open the Explorer or double-click the computer, as shown below:

2. Then click any of the “alt” keys on the keyboard. A new navigation bar with the wording of the tool is displayed in the interface, as shown below:

3. Click the Tools - Folder option, as shown below:

4. In the Folders tab, browse to the View tab bar and remove the sub-options for the extension of the known file type, as shown below:

5. Finally click the Apply button and the OK button, then again Open your computer and browse the files you want to view. Document, you can normally see the appropriate file extensions, as shown below: