Unable to create ActiveX component

using System;
using System.IO;
using System.Drawing;
using System.Configuration;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using Microsoft.VisualBasic;

class PDFThumbnailCsharp
{
    [STAThread]
    static void Main(string[] args)
    {
        // Acrobat objects
        Acrobat.CAcroPDDoc pdfDoc;        
        Acrobat.CAcroPDPage pdfPage;
        Acrobat.CAcroRect pdfRect;
        Acrobat.CAcroPoint pdfPoint;

        AppSettingsReader appSettings = new AppSettingsReader();

        string pdfInputPath = appSettings.GetValue("pdfInputPath", typeof(string)).ToString();
        string pngOutputPath = appSettings.GetValue("pngOutputPath", typeof(string)).ToString();

        string templatePortraitFile = Application.StartupPath + @"\pdftemplate_portrait.gif";
        string templateLandscapeFile = Application.StartupPath + @"\pdftemplate_portrait.gif";;

        try
        {
            // Get list of files to process from the input path
            // Could change to read list from database instead
            string[] files = Directory.GetFiles(pdfInputPath, "*.pdf");

            for (int n=0; n < files.Length; n++)
            {
                string inputFile = files[n].ToString();
                string outputFile = pngOutputPath + files[n].Substring(files[n].LastIndexOf(@"\")+1).Replace(".pdf", ".png");

                /* Could skip if thumbnail already exists in output path
                FileInfo fi = new FileInfo(inputFile);
                if (!fi.Exists) {} */

                // Create the document (Can only create the AcroExch.PDDoc object using late-binding)
                // Note using VisualBasic helper functions, have to add reference to DLL in
                // C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322\Microsoft.VisualBasic.dll
                // Will always be available as .NET framework ships with all

                pdfDoc = (Acrobat.CAcroPDDoc) Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.PDDoc", "");
                bool boolret = pdfDoc.Open(inputFile);


                int ret;
                if (boolret == true)
                {
                    ret = 1;
                }
                else
                {
                    ret = 0;
                }


                if (ret == 0)
                {
                    throw new FileNotFoundException();
                }

                // Get the number of pages (to be used later if you wanted to store that information)
                int pageCount = pdfDoc.GetNumPages();

                // Get the first page
                pdfPage = (Acrobat.CAcroPDPage)pdfDoc.AcquirePage(0);

                pdfPoint = (Acrobat.CAcroPoint)pdfPage.GetSize();

                pdfRect = (Acrobat.CAcroRect) Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.Rect", "");

                pdfRect.Left = 0;
                pdfRect.right = pdfPoint.x;
                pdfRect.Top = 0;
                pdfRect.bottom = pdfPoint.y;

                // Render to clipboard, scaled by 100 percent (ie. original size)
                // Even though we want a smaller image, better for us to scale in .NET
                // than Acrobat as it would greek out small text
                // see http://www.adobe.com/support/techdocs/1dd72.htm
                pdfPage.CopyToClipboard(pdfRect, 0, 0, 100);

                IDataObject clipboardData = Clipboard.GetDataObject();

                if (clipboardData.GetDataPresent(DataFormats.Bitmap))
                {
                    Bitmap pdfBitmap = (Bitmap)clipboardData.GetData(DataFormats.Bitmap);

                    // Size of generated thumbnail in pixels
                    int thumbnailWidth = 45;
                    int thumbnailHeight = 59;

                    string templateFile;

                    // Switch between portrait and landscape
                    if (pdfPoint.x < pdfPoint.y)
                    {
                        templateFile = templatePortraitFile;
                    }
                    else
                    {
                        templateFile = templateLandscapeFile;
                        // Swap width and height (little trick not using third temp variable)
                        thumbnailWidth = thumbnailWidth ^ thumbnailHeight;
                        thumbnailHeight = thumbnailWidth ^ thumbnailHeight;
                        thumbnailWidth = thumbnailWidth ^ thumbnailHeight;
                    }

                    // Load the template graphic
                    Bitmap templateBitmap = new Bitmap(templateFile);

                    // Render to small image using the bitmap class
                    Image pdfImage = pdfBitmap.GetThumbnailImage(thumbnailWidth, thumbnailHeight,
                                                                 null, IntPtr.Zero);

                    // Create new blank bitmap (+ 7 for template border)                         
                    Bitmap thumbnailBitmap = new Bitmap(thumbnailWidth + 7, thumbnailHeight + 7,
                                                        System.Drawing.Imaging.PixelFormat.Format32bppArgb);

                    // To overlayout the template with the image, we need to set the transparency
                    // http://www.sellsbrothers.com/writing/default.aspx?content=dotnetimagerecoloring.htm
                    templateBitmap.MakeTransparent();

                    using (Graphics thumbnailGraphics = Graphics.FromImage(thumbnailBitmap))
                    {
                        // Draw rendered pdf image to new blank bitmap
                        thumbnailGraphics.DrawImage(pdfImage, 2, 2, thumbnailWidth, thumbnailHeight);

                        // Draw template outline over the bitmap (pdf with show through the transparent area)
                        thumbnailGraphics.DrawImage(templateBitmap, 0, 0);

                        // Save as .png file
                        thumbnailBitmap.Save(outputFile, System.Drawing.Imaging.ImageFormat.Png);

                        Console.WriteLine("Generated thumbnail... {0}", outputFile);
                    }

                    pdfDoc.Close();

                    // Not sure how why it is to do this, but Acrobat is not the best behaved COM object
                    // see http://blogs.msdn.com/yvesdolc/archive/2004/04/17/115379.aspx
                    Marshal.ReleaseComObject(pdfPage);
                    Marshal.ReleaseComObject(pdfRect);
                    Marshal.ReleaseComObject(pdfDoc);
                }
            }
        }
        catch (System.Exception ex)
        {
            Console.Write(ex.ToString());
        }

    }
}