Похоже, что слушатель не запущен. Проверьте его состояние в командной строке операционной системы:
C:\Users>lsnrctl status
LSNRCTL for 64-bit Windows: Version 11.2.0.2.0 - Production on 07-OÄU-2020 22:38:28
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
64-bit Windows Error: 2: No such file or directory
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=my_server)(PORT=1521)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
64-bit Windows Error: 61: Unknown error
C:\Users>
Как видите, та же ошибка, что и у вас. Итак, начнем:
C:\Users>lsnrctl start
LSNRCTL for 64-bit Windows: Version 11.2.0.2.0 - Production on 07-OÄU-2020 22:39:13
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Starting tnslsnr: please wait...
TNSLSNR for 64-bit Windows: Version 11.2.0.2.0 - Production
<snip>
The command completed successfully
C:\Users>