Trying to "Reconnect " to database after reinstalling oracle.

Question

I was forced to reformat my hard drive for an Win XP OS recently which meant I had to reinstall Oracle 10G from scratch. I backed up all my database files as well as my init.ora files and saved the tnsnames and listener info. I've recreated my listener and service names. I did not create to initial database when I reinstalled oracle I just loaded 10g and wanted to re-connect with all of my pre-exisitng databases. So the only service in the services window for Oracle is the Listener service that I created. At this point I can do a TNSPING on my service, however I'm having trouble connecting to my database. SQLplus works but when I use the service to connect to my database i get a ORA-12560: TNS:protocol adapter error. I've tried to use configuration assistant but with no luck.
Basically what did I miss? How can I let 10g know that there are database files with control files in a directory and an init.ora file with which to connect to? Do I have to create all the services in XP myself? What must I still do?
Thanks in advance.

Answer 1

I checked my listener and it's the same configuration as the one I have backed up except the key is of by one digit. It's as follows:
OLD listener.ora file:
# listener.ora Network Configuration File: C:\oracle\product\10.2.0\db_1\network\admin\listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = C:\oracle\product\10.2.0\db_1)
(PROGRAM = extproc)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
(ADDRESS = (PROTOCOL = TCP)(HOST = OSI2.com)(PORT = 1521))
New Listener.ora file:
# listener.ora Network Configuration File: c:\oracle\product\10.2.0\db_1\network\admin\listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = c:\oracle\product\10.2.0\db_1)
(PROGRAM = extproc)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = OSI2.com)(PORT = 1521))
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
)