“Maximum request length exceeded” error even after setting maxAllowedContentLength

Question

I'm using IIS 6.2 and my solution has a file-upload control and trying to upload a bunch of images but i get this error.I have searched the internet and got a lot of solutions but none of them worked.

I have applied maxAllowedContentLength="1073741824" but still get the same error.

protected void lnkbtnUpload_Click(object sender, EventArgs e)
{
    try
    {
        foreach (HttpPostedFile objHttpPostedFile in fuUpload.PostedFiles)
        {
            string FileName = objHttpPostedFile.FileName;
            string FileType = objHttpPostedFile.ContentType;
            Stream fs = objHttpPostedFile.InputStream;
            BinaryReader br = new BinaryReader(fs);
            Byte[] bytes = br.ReadBytes((Int32)fs.Length);

            using (SqlConnection con = new SqlConnection(ConnectionString))
            {
                con.Open();
                SqlCommand cmd = new SqlCommand("uspInsertImage", con);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.Add("Filename", SqlDbType.NVarChar).Value = FileName;
                cmd.Parameters.Add("FileType", SqlDbType.NVarChar).Value = FileType;
                cmd.Parameters.Add("ImageStream", SqlDbType.VarBinary).Value = bytes;
                cmd.Parameters.Add("DateCreated", SqlDbType.DateTime).Value = DateTime.Now;
                int i = cmd.ExecuteNonQuery();
                con.Close();
            }

            BindImage();
        }
    }
    catch(Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
}

My Web.Config File

<system.web>
  <compilation debug="true" targetFramework="4.5" />
  <httpRuntime targetFramework="4.5" />
</system.web>    
<system.webServer>
  <security>
    <requestFiltering>
      <requestLimits maxAllowedContentLength="4073741824" />
    </requestFiltering>
  </security>

Answer 1

requestLimits settings have been added since IIS 7.0.

For IIS 6 you need to use:

<system.web>
    <httpRuntime maxRequestLength="1048576" executionTimeout="100000" />
</system.web>

This allows a file upload of 1 GB and it will time out after 100,000 seconds, or 27.8 hours.

Answer 2

Maximum request limited is there to protect your website against denial of service attacks so it's best to expand the file-size limit for specific directories rather than your entire application you can do it with

<location path="Upload">
<system.web>
    <httpRuntime executionTimeout="110" maxRequestLength="1048576" />
</system.web>

and you can use the code below to show a warning to the users when they try to upload something higher than max limit, adding a warning will improve your website UX

    System.Configuration.Configuration config = WebConfigurationManager.OpenWebConfiguration("~");
HttpRuntimeSection section = config.GetSection("system.web/httpRuntime") as HttpRuntimeSection;
double maxFileSize = Math.Round(section.MaxRequestLength / 1024.0, 1);
FileSizeLimit.Text = string.Format("Make sure your file is under {0:0.#} MB.", maxFileSize);

Note: maxRequestLength is measured in kilobytes, which is why the values differ in this config example. (equivalent to 1 GB.)