ora 24314 service handle not initialized

Hello all,
I was working with an 8.1.6 DB and I needed to migrate to 8.1.7. As I was newbie (And i keep on being that) I copied all the files related with the DB (control, dbf..). I created a new DB with the same name and path as the 81.6 one and replaced its files with the one I saved previously.
Maybe it´s a madness solution...
My problem now is that I get the 'ora 24314 service handle not initialized' error. I have read something in metalink, note 122183.1, just the point in which it sais 'If the ORACLE_HOME points to the 8.1.7 software yet the database

      was created with 8.1.6 or 8.1.5, then this error can occur' is my problem.
I don´t know how could I resolve it. Could somebody orient me? Or if you think it´s impossible to recover, please, tell me? A lot of thanks

begin:vcard
n:Jimenez;Beatriz Martinez
x-mozilla-html:FALSE
org:Fundación CIDAUT;Departamento de Informática adr:;;Parque Tecnológico de Boecillo p.209;Boecillo;Valladolid;47151;Spain version:2.1
email;internet:beamar_at_cidaut.es
title:Ingeniera Informática
fn:Beatriz Martínez Jiménez
end:vcard Received on Fri Nov 16 2001 - 08:17:05 CST