the ip address is bad or unreachable - confirm you can PING
then confirm the listener is up and going, and on the port/service you're trying
I have already gone through the steps mentioned in the forum "https://community.oracle.com/thread/3519434"
Please help me out.
Please help us out - what were the results when you tried EACH of those things in that link?
That exception means the credentials you provided do NOT match any DB at any server that can be found.
Post the details of the connection and parameters you are using:
1. OCI or thin driver?
2. what host name and port etc?
3. can you connect with sql*plus?
4. are you using a VM?
5. can you ping the server?
6. can you tnsping the database?
Just saying you tried something but it didn't work isn't enough. You need to SHOW US, not just tell us:
1. WHAT you did
2. HOW you did it
3. WHAT results you got