The appearance of ORA-12557 is sometimes related to oracle_home not set or set an error

ORA-12557 The process of resolution

ORA-12557:	Tns:protocol Adapter Not loadable
Cause:	On some platforms (such as OS/2) protocol adapters are loadedat. If the shared library (or DLL) for the protocoladapter are missing or one of its supporting libraries are missingthen this E Rror is returned.
Action:	For further details, turn on tracing and Reexecute theoperation. The trace file would include the name of the Sharedlibrary (or DLL) that could is loaded.

1. Make sure the %oracle_home%/bin directory (that is, directory) is in your (environment variable) path.//that ORA-12557 appears sometimes with Oracle_ Home not set or set error related
2. Make sure the protocol are typed/specified correctly in your
Tnsnames.ora file or whatever source you ' re using to resolve service
Names.
3. TCP is the default protocol and are installed by default. If
You ' re using the something different (like SPX) Make sure for you installedthe
Protocol adapter.
4. Make sure TOAD are using the correct oracle_home if youhave
Multiple homes installed

-------------------------environment is loaded with two instances, a 9i, a 10G

Sql> Conn Sys/admin@c11 assysdba;
ERROR:
Ora-12557:tns:protocol Adapter Not loadable

------Lsnrctl>status the error.

Message 1053 not found; No message file for Product=network,facility=tnstns-12538:message

12538 not found; No message file for Product=network,facility=tns
Tns-12560:message 12560 not found; No message file Forproduct=network, Facility=tns
Tns-00508:message 508 not found; No message file Forproduct=network, Facility=tns

---------------

1. Reconfigure the Monitor

2, Echo%oracle_home% see if the open instance is in this directory

If set ORACLE_HOME=D:ORACLEORA92 is not set

Above excerpt: http://steve352.itpub.net/post/33251/306560

Happened to have a friend also installed 9I and 10 also appeared ORA-12557, modify Oracle_sid error Still, modify oracle_home for the current database oracle_home after the problem solved.

Description

1. Oracle_home is the root directory of software installed by ORACLE. Oracle based on this root directory, you can relative location of other relevant programs where

(Oracle_home if it is not correct, then such as starting a database or landing when the relevant program can not find the error)

2, SID is the establishment of a database, the identifier of this database

3, if there are 2 or more instance in one version, then how to set Oracle_sid.

In fact, set ORACLE_SID in the environment variable only in the conn without @ when the default connection database, so only one, in fact, can not set. However, if there are 2 or more instance in one version, Conn must take @sid_name (Sid_name is a network service name, note that this time is required to open the monitor lsnrct start)

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Ora-12557:tns:protocol Adapter Not loadable
Environment background: This machine has multiple Oracle instances (11,9i), and Oracle of the attached server is 9i

Antecedent: I have just entered the company, so the computer domain account is not down in the approval, used before that person's account login system, all normal.
Consequences: My account down, so I replaced my own account login computer, all configuration reset, this time all the environment variables reset, when all the environment variables set and before, think it's done.

Open Plsql, connect Oralce, reported this mistake: ORA-12557, on the internet to find a large pile, are not my cause of the problem, engaged in the afternoon, it is not possible, looking for the company to see the great God, the great God went straight to the theme, point open Plsql, help-> support information, See the OCI Library in preferences with the 11g Oci.dll, at a glance.

So open preference files in the 2 Default.ini file view, the Ocifile change into a 9i path (ocifile=d:\oracle9i\ora90\bin\oci.dll), fix.


Khan, ~~~~~~~~~~ me all afternoon, the great God has been doing this for 1 minutes.