I need to find out if is there any other way to get the FilePath from drive D:
The code below using Server.MapPath take me to the C: drive per default, but I want to get the D: drive first, then been able to upload any file from D:// drive, my web app is in C: drive.

protected void Button1_Click(object sender, EventArgs e)
        {
            if (!FileUpload1.HasFile) //Validation
            {
                Response.Write("No file Selected"); return;
            }
            else
            {
                // Read and populate textboxes from Index.txt
         
                string indexFilePath = Server.MapPath("~/index.txt");  //Need to change path
                //Server.MapPath("~//wcupobproc1-a/Old_Check_Images/index.txt");
                PopulateTextBoxes(indexFilePath);

                // Extract values from textboxes
                string acctNumber = txtAcctNumber.Text;
                string chkNumber = txtChkNumber.Text;
                string imgDate = txtDate.Text;
                string imagePath = ViewState["ImagePath"].ToString();

                // Convert the image to byte array
                byte[] imageData = ConvertImageToByteArray(imagePath);

                // Insert the data into the database
                using (SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["DBCS"].ToString()))
                {
                    connection.Open();
                    SqlCommand cmd = new SqlCommand("INSERT INTO chkImages (acctNumber, chknumber, imgdate, imageData) VALUES (@acctNumber, @chknumber, @imgdate, @imageData)", connection);

                    cmd.Parameters.AddWithValue("@acctNumber", acctNumber);
                    cmd.Parameters.AddWithValue("@chknumber", chkNumber);
                    cmd.Parameters.AddWithValue("@imgdate", imgDate);
                    cmd.Parameters.AddWithValue("@imageData", imageData);

                    cmd.ExecuteNonQuery();
                    connection.Close();

                    Response.Write("Image has been Added");
                }
            }
        }

I used Server.Mappath, but it is default to C: because my web app is in C: drive.