The listener failed to start a dedicated....

Hello list,
Yesterday I had a problem with my computer, and I had to repair my NT installation, and I lost all the data stored in the registers ( NT services....). As I don´t have the services installed, I can´t start/stop them from NT services.
When I try to start the listener from the command line, I get no error, but when trying to connect any of the databases I get the error The listener failed to start a dedicated server process. I need help for:
 first and urgent, how starting the listener correctly, I have
used the following command:
                   

lsnrctl start XXXX
    or any idea about why my database can´t be
connected.
second:
    How stablishing the start/stop as NT services.
A lot of thanks, for any help you cold give me.
 

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n:Jiménez;Beatriz Martínez Jiménez
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url:www.cidaut.es
org:Fundación CIDAUT;Departamento Informática version:2.1
email;internet:beamar_at_cidaut.es
title:Ingeniera Informática
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end:vcard Received on Fri Mar 30 2001 - 06:07:26 CST