Change the error handling message for read_file_meterpreter(), because this one is easier to understand

lib/msf/core/post/file.rb

@@ -168,7 +168,7 @@ protected
 		begin
 			fd = session.fs.file.new(file_name, "rb")
 		rescue ::Rex::Post::Meterpreter::RequestError => e
-			print_error("Failed to open file: #{e.class} : #{e}")
+			print_error("Failed to open file: #{file_name}")
 			return nil
 		end