However, one must clean up the registry, which is not easy. All the things are easy for the people who know them well. Last time, our Oracle certified DBA failed in fixing the problem but we urgently needed to set up the DB for the prototyping. Finally, we formatted harddisk!
I myself have an Oracle running at home. I did not personallly fall into the problem. Thank you again, my friends's friend. By the way, I don't encourage people to touch windows registry.