I have just switched to a new PC. I have downloaded SQL Developer version 220.127.116.11 and have put connections to my databases. I can connect to every database except one. When I try to connect to it, It gives me the below mentioned error:
An error was encountered performing the requested operation:
lo exception: The Network Adapter could not establish the connection
Vendor code 17002
I can connect to it from my old computer and there's no problem in the database connection. Everythings fine with the tnsnames.ora and sqlnet.ora because all other connections work. I have copy-pasted the same ora files from my old computer. I'm just not able to understand why there's a problem with just this one database.
I can ping this database but when i do tnsping, it gives me the error : TNS-12535: TNS:operation timed out.
I am able to ping and tnsping all other databased.
Do you have any idea what problem it could be. I mean, the database is not down and the connection works fine in my old PC. I have checked and rechecked my tnsnames, ip address etc but just cannot understand where the problem might be. If there were any problem with my tnsnames.ora then other databases shouldnt have connected but they do and I hv copied exactly the same tnsnames.ora as my old PC.
Any advises. Thanks.
I'm afraid I can't offer a solution to your problem. However when I read your problem I thought this must be an entry I put in myself and forgot about, as it mirrors almost exactly my situation and it also occured on the 5 April.
The only difference is that my wasn't a new pc, but a laptop that had some VPN software installed on it which cause connection problem, we think it might be related to some firewall settings and/or connectivity to servers which are situated on another site, I can only offer these as possible issues in your case.
At the moment I've had to disable the VPN software so that I can connect.
I see that many of you have resolved this issue now, but I thought I would add my resolution to the thread as well.
Having not logged into my db for a couple of months, i decided to fire up sqldeveloper to find I was receiving this same error as the rest of you. However the last time i tried it there was no such error and I dont recall anything changing in between.
I am running the DB on my vista pc and have sqldeveloper on the same machine.
Long story short, sqldeveloper was trying to connect to "localhost" (which it always had done successfully in the past), however when I checked my tnsnames.ora file, I noticed the address was my pc's actual windows name. I changed the setting in sqldeveloper from localhost to this name and it connected fine.
Curiously I was still able to connect to the DB through sqlplus using localhost/1521/orcl as the connection string.
The only thing that I can think of, however unlikely, that may have caused this was changing from Norton Security Suite to Avast antivirus and Windows Firewall. It doesnt sound likely, but I dont really trust what these "security" programs do in the background.