C#

'The 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine

private void ConnectToAccess(string accessDB)
{
    try
    {
        connString = $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={accessDB};Persist Security Info = False;";
        acccessConn = new OleDbConnection(connString);
        acccessConn.Open();
    }
    catch (Exception e)
    {
        MessageBox.Show(e.ToString(), "Error", MessageBoxButton.OK, MessageBoxImage.Exclamation);
    }
}

private static DataSet ToDataSet(string excelFile, int startRecord = 0, int maxRecord = -1, string condition = "")
{
    DataSet result = new DataSet();

    string connString = connString = $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={excelFile};Extended Properties=Excel 12.0;HDR=No;IMEX=1";
    using (OleDbConnection connection = new OleDbConnection(connString))
    {
        try
        {
            connection.Open();  //==== THROWS HERE

            DataTable schema = connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);

            foreach (DataRow drSheet in schema.Rows)
            {
                if (drSheet["TABLE_NAME"].ToString().Contains("$"))
                {
                    string s = drSheet["TABLE_NAME"].ToString();

                    if (s.StartsWith("'")) 
                    {
                        s = s.Substring(1, s.Length - 2);
                    }
                    var command =  new OleDbDataAdapter(string.Join("", "SELECT * FROM [", s, "] ", condition), connection);

                    DataTable dt = new DataTable();

                    if (maxRecord > -1 && startRecord > -1)
                    {
                        command.Fill(startRecord, maxRecord, dt);
                    }
                    else
                    {
                        command.Fill(dt);
                    }

                    result.Tables.Add(dt);
                }
            }

            return result;
        }
        catch (Exception ex)
        {
            throw;
        }
        finally
        {
            connection.Close();
        }
    }
}

/// <summary>
/// Deletes a Role.
/// </summary>
/// <param name="id">The Role id.</param>
public void DeleteRole(int id)
{
    try
    {
        var role = (from u in dataContext.Roles
                    where u.Id == id
                    select u).FirstOrDefault();
        var hasUsers = (from u in dataContext.Users
                        where u.RoleId == id
                        select u).Any();
        if (hasUsers)
        {
            //<==== THIS SHOULD BE SEEN BY THE USER
            throw new Exception($"The role '{role.RoleName}' cannot be deleted because it has users assigned to it." );
        }
        else
        {
            if (role != null)
            {
                role.IsDeleted = true;
                dataContext.SubmitChanges();
            }
        }
    }
    catch (Exception)
    {
        //<==== IF HERE, SOMETHING ELSE WENT WRONG, SO LET THE GLOBAL 
        //      EXCEPTION HANDLER HANDLE IT
        throw;  
    }
}

 <span id ="long"></span>
<script type='text/javascript' id="weather-link" src='https://darksky.net/widget/default/></script>
    <script>const weatherLink = $("#weather-link");
    weatherLink.html("<span id=\"" + response.latitude + "," +response.longitude + "\">/uk12/de.js?width=100%&height=350&title=Basel&textColor=333333&bgColor=FFFFFF&transparency=false&skyColor=undefined&fontFamily=Default&customFont=&units=uk&htColor=333333<Color=333333&displaySum=yes&displayHeader=yes</span>");
    weatherLink.attr("src", weatherLink.attr("src") + response.city);</script>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>

          $("#long").html(response.latitude   + ", " + response.longitude );

    $("#response").html(JSON.stringify(response, null, 4));
  }, "jsonp");
</script>