I am trying to connect to a remote Oracle 12c database from a client machine that has 11g oracle drivers for ODBC. I can reach to remote machine through ping but can not Telnet the remote machine on port 1521 neither the TNSPING succeeds. When I try test the ODBC connection using my TNS service name I get the TNS timeout error ORA-12170. I can see that the traffic is allowed in the firewall in between.While the same client machine is able to connect to another oracle database with another TNS entry. but on a another port not 1521 OS is Windows 2008 R2 and the complete message is
ORA-12170 TNS : Time out occurred.