Hi all,  i create a member register usercontrol load by macros and when every input are empty and click the create user button, it came out below, what i expect is a reload or error message lable. should i over ride any classes? or any idear , i am so new on Umbraco.

 it looks like catching username as the loginName

i am using Umbraco 6.01

Server Error in '/' Application.

The username of a Member must be different from an emptry string
Parameter name: loginName

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: The username of a Member must be different from an emptry string
Parameter name: loginName

Source Error:

Stack Trace:

[ArgumentException: The username of a Member must be different from an emptry string
Parameter name: loginName]
   umbraco.cms.businesslogic.member.Member.GetMemberFromLoginName(String loginName) +509
   umbraco.providers.members.UmbracoMembershipProvider.CreateUser(String username, String password, String email, String passwordQuestion, String passwordAnswer, Boolean isApproved, Object providerUserKey, MembershipCreateStatus& status) +30
   System.Web.UI.WebControls.CreateUserWizard.AttemptCreateUser() +412
   System.Web.UI.WebControls.CreateUserWizard.OnNextButtonClick(WizardNavigationEventArgs e) +226
   System.Web.UI.WebControls.Wizard.OnBubbleEvent(Object source, EventArgs e) +586
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +52
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3691