关于服务器运行错误

我本地测试好了，一放到服务器就错误，这个方法报错，
估计这个“ System.Drawing.Image ”使用错误，FileInfo这个对象也不能使用，郁闷。不知道服务器需要怎么配置。请大侠们帮我解决。最好详细一点服务器配置
public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
        {
            System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);
            int towidth = width;
            int toheight = height;
            int x = 0;
            int y = 0;
            int ow = originalImage.Width;
            int oh = originalImage.Height;            switch (mode)
            {
                case "HW"://指定高宽缩放（可能变形）                
                    break;
                case "W"://指定宽，高按比例                    
                    toheight = originalImage.Height * width / originalImage.Width;
                    break;
                case "H"://指定高，宽按比例
                    towidth = originalImage.Width * height / originalImage.Height;
                    break;
                case "Cut"://指定高宽裁减（不变形）                
                    if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
                    {
                        oh = originalImage.Height;
                        ow = originalImage.Height * towidth / toheight;
                        y = 0;
                        x = (originalImage.Width - ow) / 2;
                    }
                    else
                    {
                        ow = originalImage.Width;
                        oh = originalImage.Width * height / towidth;
                        x = 0;
                        y = (originalImage.Height - oh) / 2;
                    }
                    break;
                case "pp":
                    if (originalImage.Width < width && originalImage.Height < height)
                    {
                        //对宽度进行处理                        //不用缩放
                        towidth = width;
                        toheight = height;
                    }
                    else if (originalImage.Width < width && originalImage.Height >= height)
                    {
                        //高型图片                        toheight = height;
                        towidth = originalImage.Width / originalImage.Height;
                    }
                    else if (originalImage.Width >= width && originalImage.Height < height)
                    {
                        //长型图片                        toheight = originalImage.Height / originalImage.Width;
                        towidth = width;
                    }
                    else
                    {
                        if (towidth > toheight)
                        {
 
                        }
                        else
                        {
 
                        }
                    }
                                        break;
                default:
                    break;
            }            //新建一个bmp图片
            System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);            //新建一个画板
            System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);            //设置高质量插值法
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;            //设置高质量,低速度呈现平滑程度
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //清空画布并以透明背景色填充
            g.Clear(System.Drawing.Color.Transparent);            //在指定位置并且按指定大小绘制原图片的指定部分
            g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
                new System.Drawing.Rectangle(x, y, ow, oh),
                System.Drawing.GraphicsUnit.Pixel);            try
            {
                //以jpg格式保存缩略图
                bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
            }
            catch (System.Exception e)
            {
                throw e;
            }
            finally
            {
                originalImage.Dispose();
                bitmap.Dispose();
                g.Dispose();
            }
        }