Question

Source Error: 

Line 55:                MembershipUser User = Membership.GetUser(UserNameTextBox.Text);
Line 56:   
Line 57:                Object UserGUID= User.ProviderUserKey; //error appeared here
Line 58:   
Line 59:                DataSource.InsertParameters.Add("UserId", UserGUID.ToString());

I had a additional steps in createuserwizard, and upon completing the form, it would stored user info inside the DB. However this error occured :

Object reference not set to an instance of an object.

I had also set a breakpoint to link 55, 57, 59. And from line 57, User are null, they could not get the User from the DB.

Code behind :

protected void CreateUserWizard1_CreatedUser(object sender, System.Web.UI.WebControls.LoginCancelEventArgs e)
    {  
       MSCaptcha.CaptchaControl Captcha1 = (CreateUserWizardStep1.ContentTemplateContainer.FindControl("Captcha1") as MSCaptcha.CaptchaControl);

       TextBox txtCaptcha = (TextBox)CreateUserWizardStep1.ContentTemplateContainer.FindControl("txtCaptcha");
       Label Captchalbl = (Label)CreateUserWizardStep1.ContentTemplateContainer.FindControl("Captchalbl");

       Response.Write(txtCaptcha.Text); 

           Captcha1.ValidateCaptcha(txtCaptcha.Text.Trim()); 

           if (!Captcha1.UserValidated)
           {

                Captchalbl.Text = "InValid";

               e.Cancel = true;
           } 
            else
           {
               Captchalbl.Text = "Valid";

               TextBox UserNameTextBox =
              (TextBox)CreateUserWizardStep1.ContentTemplateContainer.FindControl("UserName");

               SqlDataSource DataSource =
                   (SqlDataSource)CreateUserWizardStep1.ContentTemplateContainer.FindControl("InsertExtraInfo");

               MembershipUser User = Membership.GetUser(UserNameTextBox.Text);

               Object UserGUID= User.ProviderUserKey; //here is link 57. 

               DataSource.InsertParameters.Add("UserId", UserGUID.ToString());

               DataSource.Insert();

            }
   }

Answer 1

Although this method name is “CreateUserWizard1_CreatedUser”, I can see it is for the CreatingUser event because of its signature. During this event the user has not been created yet. Use the CreatedUser event for that.