ORA-12528: TNS:Listener: All Appropriate instances are blocking new connections

• Go to the database server box
• Navigate to the bin folder and launch SQLPLUS (Usually C:\app\rmanni\product\11.1.0\db_1\BIN )

Luanch sqlplus and connect to the database as SYS without using @TNSAlias

ex: conn sys/sys as sysdba

Once you are in, do a

• Shutdown
• Startup

You are good to go.

Oracle 11g Installation: File not found

Oracle 11g Release 2 Installation files contains 2 zip files.

1. win32_11gR2_database_1of2.zip
2. win32_11gR2_database_2of2.zip

You need to unzip both the files into the same location. Unzipping the first one, will not unzip the second file.

Pretty lame, but you have to unzip both.

ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

ORA-12514: TNS:listener does not currently know of service requested in connect descriptor is the most common and most frustrating error in Oracle

What it means is, In tnsnams.ora, the service_name parameter is in correct or not available

TNS_Service =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = machine_name)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = Database_Name)
)
)

In my instance, I have Oracle hosted on a Windows box, and my OracleServiceDatabase_Name
was not started.

Once I started the Windows service , I was able to connect to the database

Start->Run->Services.msc

Locate the OracleServiceDatabase_Name, and right click and start the service.