Unable to enable URL-rewriting for my website

[Gregouze]

I am using http://www.urlrewriter.net it should load http://www.mywebsite.com/viewtopic.aspx?id=23scs34But instead of loading the page its showing 404 error. So what can be the problem? Please tell me ASAP.Moreover for generating the URL I am calling this function:\[code\]public static string GenerateURL(object Title, object strId) { string strTitle = Title.ToString(); #region Generate SEO Friendly URL based on Title //Trim Start and End Spaces. strTitle = strTitle.Trim(); //Trim "-" Hyphen strTitle = strTitle.Trim('-'); strTitle = strTitle.ToLower(); char[] chars = @"$%#@!*?;:~`+=()[]{}|\'<>,/^&"".".ToCharArray(); strTitle = strTitle.Replace("c#", "C-Sharp"); strTitle = strTitle.Replace("vb.net", "VB-Net"); strTitle = strTitle.Replace("asp.net", "Asp-Net"); //Replace . with - hyphen strTitle = strTitle.Replace(".", "-"); //Replace Special-Characters for (int i = 0; i < chars.Length; i++) { string strChar = chars.GetValue(i).ToString(); if (strTitle.Contains(strChar)) { strTitle = strTitle.Replace(strChar, string.Empty); } } //Replace all spaces with one "-" hyphen strTitle = strTitle.Replace(" ", "-"); //Replace multiple "-" hyphen with single "-" hyphen. strTitle = strTitle.Replace("--", "-"); strTitle = strTitle.Replace("---", "-"); strTitle = strTitle.Replace("----", "-"); strTitle = strTitle.Replace("-----", "-"); strTitle = strTitle.Replace("----", "-"); strTitle = strTitle.Replace("---", "-"); strTitle = strTitle.Replace("--", "-"); //Run the code again... //Trim Start and End Spaces. strTitle = strTitle.Trim(); //Trim "-" Hyphen strTitle = strTitle.Trim('-'); #endregion //Append ID at the end of SEO Friendly URL strTitle = strTitle + "-" + strId; return strTitle; }\[/code\]