File Function:

The File function checks for the existence of a file. Pathname must be a path to a file, including extension. Returns True if the file exists and False if it does not exist.

boolean = File(pathname)
Example Usage:
<% = File( server.mappath("/New Folder/file.asp") ) %>
ASP Source Code:
Private Function File(byVal pathname)
	Dim objFSO
	Set objFSO = Server.CreateObject("Scripting.FileSystemObject")
	File = objFSO.FileExists(pathname)
	Set objFSO = Nothing
End Function