 <p>I tried replacing the path of the input and output by one <strong>without any space</strong> and it now works ! Here is the code I ended up using :</p> <pre><code>using Ghostscript.NET.Rasterizer; private void button6_Click(object sender, EventArgs e) { int desired_x_dpi = 96; int desired_y_dpi = 96; string inputPdfPath = @"D:\Public\temp\rasterizer\FOS.pdf"; string outputPath = @"D:\Public\temp\rasterizer\output\"; using (var rasterizer = new GhostscriptRasterizer()) { rasterizer.Open(inputPdfPath); for (var pageNumber = 1; pageNumber &lt;= rasterizer.PageCount; pageNumber++) { var pageFilePath = Path.Combine(outputPath, string.Format("Page-{0}.png", pageNumber)); var img = rasterizer.GetPage(desired_x_dpi, desired_y_dpi, pageNumber); img.Save(pageFilePath + "ImageFormat.Png"); } } } </code></pre>