Sunday, 13 May 2012

* ORA-12560: TNS: protocol adapter error

    One of the most common Oracle errors post installation.....When I sign on I get the error "ORA-12560:TNS:protocol adapter error"...

Enter password:
ERROR:  ORA-12560: TNS:protocol adapter error

Enter password:
ERROR:  ORA-12560: TNS:protocol adapter error

Cause: A generic protocol adapter error occurred. 

Action: Check addresses used for proper protocol specification. Before reporting this error, look at the error stack and check for lower level transport errors. For further details, turn on tracing and re-execute the operation. Turn off tracing when the operation is complete.



Workaround:

1. Apply new patches if any and check for the latest  updates
2. Make sure your $ORACLE_HOME and $PATH variables are set to correct values
3. Check the NTFS permissions on the client PC
4. Make sure that TNS_ADMIN account is set appropriately
5.Check for windows network firewall blockages
6. Check for the value of ORACLE_SID parameter in registry settings
7. Finally looks for the Oracle service start up in windows services

Hope this helps and wish you good luck!!!!!!!!!!!!!