Creating a gif with gnuplot: Gif doesn't play

Question

I want to do a gif animation with gnuplot so I wrote:

set terminal gif size 1000,800 animate delay 6
set output 'foobar.gif'

set xrange [0:64]
set yrange [0:64]

do for [i=100:5000:100] {
  plot sprintf('folder\name%d.dat',i) u 2:3:(20*$5):(20*$6) with vectors filled head lw 3, 
       sprintf('folder\name%d.dat',i) u 2:3 with points pt 7 ps 2 
}

The problem is that, although it doesn't show any error nor warning, when I open the gif file with chrome or ie it doesn't play the gif. What's wrong with it?

I'm using windows 7 x64 with gnuplot 4.6 patch 0. Inside the folder "folder" there is a collection of 50 files that have only 1 line of text. An example of these lines is:

0 1.000000e+00 1.000000e+00 1.867146e+00 6.411429e-18 -1.234238e-17 1.106649e-02 8.568272e-18 -9.160938e-18 -3.999043e-18

Answer 1

Right. It would sound very stupid but I was thinking that I was plotting the correct columns and instead, I was plotting two columns that always have the same value... Thank for your effort. –