This method uses ExifExtractor code referenced below from CodeProject.com.

public static Bitmap AutoRotateImage(Bitmap bmp)
{
  // Get source from: http://www.codeproject.com/KB/graphics/exifextractor.aspx?fid=207371
  var exif = new EXIFextractor(ref bmp, "n");
  switch (int.Parse(exif["Orientation"].ToString()))
  {
    case 1:
      bmp.RotateFlip(RotateFlipType.RotateNoneFlipNone);
      break;
    case 2:
      bmp.RotateFlip(RotateFlipType.RotateNoneFlipX);
      break;
    case 3:
      bmp.RotateFlip(RotateFlipType.Rotate180FlipNone);
      break;
    case 4:
      bmp.RotateFlip(RotateFlipType.Rotate180FlipX);
      break;
    case 5:
      bmp.RotateFlip(RotateFlipType.Rotate90FlipX);
      break;
    case 6:
      bmp.RotateFlip(RotateFlipType.Rotate90FlipNone);
      break;
    case 7:
      bmp.RotateFlip(RotateFlipType.Rotate270FlipX);
      break;
    case 8:
      bmp.RotateFlip(RotateFlipType.Rotate270FlipNone);
      break;
    default:
      bmp.RotateFlip(RotateFlipType.RotateNoneFlipNone);
      break;
  }
  return bmp;
}

When running inside a foreach() statement this error will occur unless you convert the Entity objects into a List.

// Original code that errors:
myFlickr = FlickrAuthentication();
using (FlickrPicsModel.FlickrPicsEntities dbx = new FlickrPicsModel.FlickrPicsEntities())
{
  foreach (FlickrPicsModel.Pic pic in dbx.Pics.Where(t => t.ProcessDate.Value >= MinDate &&
    t.FlickrPhotoId == null))
  {
    pic.FlickrPhotoId = myFlickr.UploadPicture(string.Concat(pic.FilePath, @"\", pic.FileName)
      , pic.FlickrTags, pic.FlickrTags, pic.FlickrTags + ",CS-" + pic.CheckSum.ToString());
    dbx.SaveChanges();
  }
}

// New code converting to IList:

myFlickr = FlickrAuthentication();
using (FlickrPicsModel.FlickrPicsEntities dbx = new FlickrPicsModel.FlickrPicsEntities())
{
  foreach (FlickrPicsModel.Pic pic in dbx.Pics.Where(t => t.ProcessDate.Value >= MinDate &&
    t.FlickrPhotoId == null).ToList())
  {
    pic.FlickrPhotoId = myFlickr.UploadPicture(string.Concat(pic.FilePath, @"\", pic.FileName)
      , pic.FlickrTags, pic.FlickrTags, pic.FlickrTags + ",CS-" + pic.CheckSum.ToString());
    dbx.SaveChanges();
  }
}

Error Message: New transaction is not allowed because there are other threads running in the session.