Applicable for both WCC and Reporting databases; when you choose to use TNSNamesFile connect option. Valid TNSServerName should be present in the WCC connection.properties file.
Verify current WCC connection.properties file is pointing to a valid TNS Alias name for parameters wcc.database.tnsname and reporting.database.tnsname
Note: Location of the connection.properties file is %CA_WCC_INSTALL_LOCATION%\data\config\application\config\resources (Windows) and $CA_WCC_INSTALL_LOCATION/data/config/application/config/resources (UNIX/Linux)
If the tnsname parameters highlighted below are blank please update them according to your Oracle environment.
Example: WCC connection.properties file from a Linux server using "WCCDB" as TNS alias for WCC and Reporting databases.