If the message file is there. Then the root cause of this problem is usually the PATH.
Make sure you correctly set your PATH in your system environment.
Here is the step to check that the problem really is your PATH
C:\>set ORACLE_HOME=<your Oracle Home> (just above bin directory)
C:\>sqlplus “/ as sysdba”
If you can run sqlplus then you know for sure that there is something wrong with your PATH.
Go to your system environment and create ORACLE_HOME. Its value should be directory to your oracle home ( mine is C:\Oracle\product\11.2.0\client_1 , make sure your dont leave a trailing ‘\’ or ‘;’ )
Then edit your PATH and put %ORACLE_HOME$\bin; at the leftmost of your PATH value.
Restart cmd and try sqlplus. It should work now..
Technically this error would happen when your PATH variable in your system does not include path to directory of Oracle Instant Client.
However, there are times, such as my case, that you are quite sure that system PATH is correctly set and everything is right. But still, the problem persist.
The solution that work for me is to copy files from Instant Client directory and put it to apache/bin folder. First, I copy all the files there, restart my PC and the problem is solved. However I dont want my apache folder to look messy so I try to remove files that are not used and it turns out that I only need two files, oci.dll and oraociei11.dll
Still, I don’t understand why setting path to Oracle home does not work?
Here is my setup :
Windows 7, 64 bit
Oracle11g, 32 bit
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