Windows uses what is known as “file extensions” (the letters after the ‘.’ in the filename) to determine how to handle the file. For example, “.exe” files are executable programs, “.doc” are documents (typically MS-Word), and “.qbw” are QuickBooks data files.
Out of the box, Windows defaults to hiding the file extension in folder listings, instead relying on the file’s icon to convey the file type to the user. The “bad guys” have taken advantage of this, by making you think the file is of one type, when it’s really an executable program designed to infect your system.
Fortunately, it’s an easy fix.