When you look at a file name in Windows Explorer you may have noticed that it is not very informative as to what type of file it actually is; in other words, just by looking at it, you don't know whether it is an .ini; .exe; .docx or some other type of file. The file extensions are, by default, simply not shown. The instructions below will show you how to disable this option and get Vista o show its hidden file extensions.
2/ From the Windows Explorer main toolbar, Click Organize.
3/ From the Drop Down Menu that appears, Click Folder and Search Options.
4/ Once the Folder Options window opens, Click on the View tab.
5/ In the Advanced Settings section of the Folder Options window look for a section marked Hidden Files and Folders This should be easy to locate because it has a yellow folder to highlight it.
6/ Including the hidden files and folders line, count down Four (4) lines.
7/ You should now see an option marked Hide Extensions For Known File Types.
8/ To the left of this option you will see a box with a check mark (tick) inside it.
9/ Position you Mouse pointer over the box and then Left Click. The check mark (tick) will now be removed.
11/ Now when you look at file names the relevant extension will also be visible.