No, NM1_PARAMETRO isn't a numeric type.

So I create a new table with two fields: SIG_CONTADOR and NUM_CONTADOR.

But the problem continue, look my new SP:

CREATE PROCEDURE SP_CT_ITEM

AS

  DECLARE @CONTADOR NUMERIC(015)

 ...

I modified my SP for:

CREATE PROCEDURE SP_CT_ITEM

AS

  DECLARE @CONTADOR NUMERIC(008)

  SET @CONTADOR = 0

  SET NOCOUNT ON

  UPDATE PARAMETRO SET

  @CONTADOR = CAST(NM1_PARAMETRO AS NUMERIC(008)),

  NM1_PARAMETRO = CAST(NM1_PARAMETRO...