We have an application running locally where we're experiencing the following error:
ORA-12514: TNS:listener does not currently know of service requested in connect descriptor
I've tested the connection using TNSPing which resolved correctly and
I tried SQLPlus to try connecting, which failed with the same error as above. I used this syntax for SQLPlus:
sqlplus username/password@addressname[or host name]
We have verified that:
- the TNS Listener on the server is running.
- Oracle itself on the server is running.
We don't know of any changes that were made to this environment. Anything else we can test?



I had this issue and the fix was to make sure in
tnsnames.oratheSERVICE_NAMEis a valid service name in your database. To find out valid service names, you can use the following query in oracle:Once I updated
tnsnames.orato:then I ran:
Success! The listener is basically telling you that whatever service_name you are using isn't a valid service according to the DB.
(*I was running sqlplus from Win7 client workstation to remote DB and blame the DBAs ;) *)