hjælp til unhandled exception.

Jeg får denne exception når jeg prøver at oprette en bruger på min hjemmeside.

The INSERT statement conflicted with the FOREIGN KEY constraint "FK_aspnet_Users_aspnet_Membership_UsersCurrentActivity". The conflict occurred in database "[Censored]", table "dbo.aspnet_Membership_UsersCurrentActivity", column 'UserId'.
The statement has been terminated.
  at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
  at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
  at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
  at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
  at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
  at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
  at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
  at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe)
  at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
  at System.Web.Security.SqlMembershipProvider.CreateUser(String username, String password, String email, String passwordQuestion, String passwordAnswer, Boolean isApproved, Object providerUserKey, MembershipCreateStatus& status)
  at System.Web.Security.Membership.CreateUser(String username, String password, String email, String passwordQuestion, String passwordAnswer, Boolean isApproved, Object providerUserKey, MembershipCreateStatus& status)
  at System.Web.Security.Membership.CreateUser(String username, String password, String email, String passwordQuestion, String passwordAnswer, Boolean isApproved, MembershipCreateStatus& status)
  at CreateUser.Button1_Click(Object sender, EventArgs e) in d:\WEB\localuser\keep-gaming.com\public_html\Createuser.aspx.cs:line 111
  at System.Web.UI.WebControls.Button.OnClick(EventArgs e)
  at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)
  at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
  at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
  at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
  at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Hvad går det lige ud på?