I used two datasource but same connectionstring.
When I used to retrieve data then it works fine (impersonation correctly).
However, when I used login asp.net control, it returned an error (below).
"Login failed for user 'USERNAME'".

Anyone has idea why I got this???

================

 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection
owningObject) +437
  System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection
owningConnection) +82
  System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection
outerConnection, DbConnectionFactory connectionFactory) +105
  System.Data.SqlClient.SqlConnection.Open() +111
  System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context,
Boolean revertImpersonate) +84
  System.Web.DataAccess.SqlConnectionHelper.GetConnection(String
connectionString, Boolean revertImpersonation) +197
  System.Web.Security.SqlMembershipProvider.GetPasswordWithFormat(String
username, Boolean updateLastLoginActivityDate, Int32& status, String&
password, Int32& passwordFormat, String& passwordSalt, Int32&
failedPasswordAttemptCount, Int32& failedPasswordAnswerAttemptCount,
Boolean& isApproved, DateTime& lastLoginDate, DateTime& lastActivityDate)
+1121
  System.Web.Security.SqlMembershipProvider.CheckPassword(String username,
String password, Boolean updateLastLoginActivityDate, Boolean
failIfNotApproved, String& salt, Int32& passwordFormat) +105
  System.Web.Security.SqlMembershipProvider.CheckPassword(String username,
String password, Boolean updateLastLoginActivityDate, Boolean
failIfNotApproved) +42
  System.Web.Security.SqlMembershipProvider.ValidateUser(String username,
String password) +83
  System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs e)
+160
  System.Web.UI.WebControls.Login.AttemptLogin() +105
  System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e)
+99
  System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +35
  System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +115
  System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)
+163
  System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String
eventArgument) +7
  System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler
sourceControl, String eventArgument) +11
  System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
  System.Web.UI.Page.ProcessRequestMain(Boolean
includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5102