/// <summary>
        /// Releases the unmanaged resources used by the <see cref="T:System.ComponentModel.Component"></see> and optionally releases the managed resources.
        /// </summary>
        /// <param name="disposing">true to release both managed and unmanaged resources; false to release only unmanaged resources.</param>
        protected override void Dispose(bool disposing)
        {
            base.Dispose(disposing);

            if (this.credentials != null)
            {
                this.credentials.Dispose();
                this.credentials = null;
            }
        }
 /// <summary>
 /// Set all properties to it's default values.
 /// </summary>
 public override void Reset()
 {
     this.target      = Application.ProductName ?? AppDomain.CurrentDomain.FriendlyName;
     this.credentials = null;
     this.caption     = null;        // target as caption;
     this.message     = null;
     this.banner      = null;
     this.saveChecked = false;
     this.flags       = CredentialsDialogFlags.Default;
 }