OS and Software > Webmasters and Developers > PHP: file_exists fails to work or pebkac?

There's no file system directory called "My Computer", so, probably not. "My Computer" is an entity in the shell namespace only. So unless your server happens to be dealing with the shell namespace, I'd suppose you don't see "My Computer".

Overall philosophy difference here: Unix tends to put non-file-system objects into the file system namespace -- like /dev/foo for example. Windows tends to put file system objects into some other namespace -- like the assorted x:\$Recycle.Bin directories show up in Explorer as "Recycle Bin", and only one of them. Not everything you see in Windows Explorer is a file.