plslq 8.0.4 Installation problem on Windows 7 64 bit

[Covina]

I installed 8.0.4 on Windows 7 64 bit pc. I am having problem logging into 11g database that resides on my pc. I get initilization error. I did some research and downloaded window 32 bit client and that did not work either. It messed up my oracle database login. I could to db from sqlplus only if I have the sid name explicitly assigned at the time of logging in
like system/manager@orcl -- it works
system/manager -- it won't work -- i get ERROR:
ORA-12560: TNSrotocol adapter error.
I was unable to login as sys as sysdba and had to drop the whole database and reinstall the whole database.
Is there any step by step instructions you can provide so that I can have the pl/sql developer installed on my pc.

Thanks
Covina

 

[Marco Kalter]

Can you go to Help > Support Info, press the 'Copy all pages' button on this info screen, and paste this text into an e-mail reply?