title: Procedure expects parameter '@params' of type 'ntext/nchar/nvarchar'
body: <p>this is my stored procedure:</p>
  
  <pre><code>ALTER PROCEDURE [dbo].[sp_Update_Projecttijden]
     @tabelnaam                    NVARCHAR(30)                , 
     @starttijd                  DATETIME,
     @eindtijd                  DATETIME,       
     @tijd                    FLOAT,
     @startid                 INT,
     @eindid          INT        
  AS
  BEGIN
  -- SET NOCOUNT ON added to prevent extra result sets from
  -- interfering with SELECT statements.
  SET NOCOUNT ON;
  
  -- Insert statements for procedure here
  -- DECLARE @DATEVARCHAR NVARCHAR(4000);
  DECLARE @SQLCommand NVARCHAR(MAX) = N'
      UPDATE ' + QUOTENAME(@tabelnaam) + N'
      SET Start = @starttijd
        , Einde = @eindtijd
        , Tijd = @tijd
        , StartID = @startid
        , EindID = @eindid
  
      WHERE StartID = @startid AND EindID=@eindid';
  
  EXECUTE dbo.sp_executesql @sqlCommand,
    ' N @starttijd DATETIME, @eindtijd DATETIME, @tijd FLOAT, @startid INT, @eindid INT'
  
  
    , @starttijd
    , @eindtijd
    , @tijd
    , @startid
    , @eindid;
  
  END
  </code></pre>
  
  <p>The error thrown is this:</p>
  
  <blockquote>
    <p>Msg 214, Level 16, State 3, Procedure sp_executesql, Line 3 Procedure
    expects parameter '@params' of type 'ntext/nchar/nvarchar'.</p>
  </blockquote>
  
  <p>I have been looking at similar questions/answers, but could not really solve my problem.
  All help is very much appreciated.</p>