Wonder what that file is? Use this site to locate the extension and find out what program(s) use that file type. Like DOC for a Word document. PDF for a portable document file, etc.
Here is the link: http://filext.com/alphalist.php?
Warning: the home page for this site is very confusing and it is easy to click on something you do not want. Ads tell you your system has a problem, when it does not. Just use the above link.