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.