[sql-server] Execute stored procedure with an Output parameter?

>Try this its working fine for the multiple output parameter:

CREATE PROCEDURE [endicia].[credentialLookup]
@accountNumber varchar(20),
@login varchar(20) output,
@password varchar(50) output
AS
BEGIN
SET NOCOUNT ON;
SELECT top 1 @login = [carrierLogin],@password = [carrierPassword]
  FROM [carrier_account] where carrierLogin = @accountNumber
  order by clientId, id
END

Try for the result: 
SELECT *FROM [carrier_account] 
DECLARE @login varchar(20),@password varchar(50)
exec [endicia].[credentialLookup] '588251',@login OUTPUT,@password OUTPUT
SELECT 'login'=@login,'password'=@password