Show file type in a library view (2010 and 2013)

The default “Name” column added to a library view is a link and drops the file extension. The icons under “Type” indicate the file extension but show a default image except for a few file types. To retain and display the extension for all files add the “Name (for use in forms)” column to the view. Open the libraryOpen the library settings
Under”Views” click the view you use
In the”Columns” options, check “Name (for use in forms)”
Change the”Position from left” number to reorder the columns as needed
Save the view.
Don’t forget, you’ll have to reselect the view in the web part’s properties for the changes to be seen.