If you are using 10g client with PL/SQL developer, you may encounter the message “Initialization error: Could not locate OCI dll” when launching PL/SQL Developer. It does not happen with the 8i client so I already suspected that it must be with the 10g client that I recently installed. Luckily, I found this thread in Oracle OTN forum and the solution seems to be easy.

All I have to do is copy a whole bunch of files from the ORAHOME folder to ORAHOMEbin. It seems like PL/SQL Developer is hardwired to find the files under the bin folder. It did the trick and my sql editor is now working. I hope it fixes yours too.

Here’s the screenshot of the files I copied. Take note that I copied them instead of just moving so as not to break anything.


16 Thoughts on “Could not locate OCI dll Error

  1. can you post the image or list what files you copied. The image is not showing. Thanks!

  2. Charlie on November 4, 2009 at 7:08 am said:

    I’ve got the same problem, but I can’t see your screen shot. Could you email it to me?

  3. Same problem here.
    I have no files in my ORAHOME folder, only subfolders. So I don’t know what to copy. Can you please publish the screenshot or mail it to me?

  4. sorry guys,! I have updated the post to include the screenshot.

  5. That’s indeed the answer. Which is kinda horrible. I have some simple Oracle client for 11g installed which already has a bin directory…alas, it contains stuff related to mts etc. What a mess…

  6. Bhageerath on January 20, 2010 at 10:42 pm said:

    Thanks man.Its working.

  7. Hi,

    I encountered the same issue with Oracle 11g when I was trying to login using PL/SQL Developer.

    I came across some steps which are worth sharing. And its clean means no ddl copying is involved.


    1) Login to PL/SQL Developer
    2) Go to Tools
    3) Click Preferences
    4) Click Connection in preferences pop-up
    5) Select “Orahome90” under Oracle Home dropdown
    6) Apply the changes
    7)Close the PL/SQL shell
    8) Login again to PL/SQL Developer

    And the error is no more.

    Hope this post is worth to all the people encountering the same problem.

    Ravi Bhatt.

    • Muthu on March 25, 2011 at 1:50 am said:

      Dear Ravi,

      I saw your response for this post. i am also facing the same problem.But i am using oracle 10g. PLSQLDeveloper version is 5.0.3 . in the prefernece menu of tools menu oraclehome doesn’t display any oracle home details.It’s EMPTY. But i can connect TOAD using my oracle 10g. it works fine. PLSQL dev not referring oracle TNS names.

      Could u pls provide solution for this ?


    • Beulah wilson on May 9, 2012 at 8:50 am said:

      Thank you Ravi :)….Your post was indeed very worth and useful to solve the prob 🙂

  8. Thanks Ravi Bhatt! The steps you provided works!

  9. Thanx a lot it works 🙂

  10. Thank you

  11. Thanks a lot.!!!!!!!
    Its working…..

  12. Thanks, had this same problem after a fresh Windows install with 11g – working again

Post Navigation