Thanks for the reply Sergey, I found out I was using a wrong syntax, this solved my problem:

SELECT dias FROM dbo.Fn_Dias('2', '020001')

Rookie's mistake :)

Enmanuel

>Enmanuel,
>
>The error message means that UDF cannot be found for whatever reason. You can use ENterprise Manger or Query Anlyzer Object Browser to see if UDF exists in the Database.
>
>>Hi all, I've created an UDF but when trying to access it I'm getting the error message
>>

>>Server: Msg 208, Level 16, State 1, Line 1
>>object name 'dbo.fn_dias' is invalid.

>>
>>to call the udf I'm using:
>>

>>select dbo.fn_dias('2','210001')
>>

>>
>>and here's the code:
>>

>>CREATE FUNCTION dbo.Fn_Dias (@pCuenta varchar(5),@pTipoMovi varchar(6))
>>RETURNS table
>> AS
>>return SELECT DATEDIFF(Day, (SELECT Fecha
>>                          FROM   Transac01
>>                          WHERE  Documento = Transac02.documento1 AND
>>				             Tipomovi = Transac02.Tipomovi1), fecha)  as dias
>>FROM      TRANSAC02
>>WHERE     (cuenta = @pCuenta) AND (tipomovi = @pTipoMovi)
>>
>>

>>
>>At this time I just don't know what I'm doing wrong, so I'd appreciate any help!
>>
>>