Connecting: "“Cannot load OCI DLL: C:\oracle\product\10.2.0\db_2\BIN\oci.dll"

64 bit Vista loaded with 64 bit Oracle Database 10.2.0.4 for Windows and Toad For Oracle 10.0.0.41. Toad Install appears to go fine. But when attempting to connect to the db, I get “Cannot load OCI DLL: C:\oracle\product\10.2.0\db_2\BIN\oci.dll”. The file is there. I have googled on this and found some saying Toad is 32 bit and does not work with 64 bit Oracle, but have found other entries saying Toad works with both 32 bit and 64 bit Oracle. I’ve searched asktoad.com for “OCI dll” and “Cannot load OCI DLL” but finding nothing about this error. There is an entry about an error “Could not locate OCI DLL” during installation but that’s a different error message and different operation. Using SQL*Plus, I can connect to and use the db with no issues. I see in asktoad that “Toad is supported on Windows NT 4.0, 2000, XP, and 2003 clients” is this error a symptom of Toad not being supported on Vista? Any advice is appreciated.

Toad works with both 32 and 64 bit DATABASE

Toad only works with 32 bit CLIENT

If you need 64 bit client for other apps, you can install both 32 and 64 bit
client on a single machine and just tell Toad to use the 32 bit one.

Vista is no problem. Toad can work with a 64 bit Oracle server, but you have
to use a 32 bit Oracle client. We won’t have the ability to use a 64 bit
client until our development environment (Delphi) has a 64 bit version.

Toad requires a 32 bit Oracle client.

From the Toad Getting Started Guide:

Here’s a chart to summarize:

Hello Jdorlon

I have the same problem : Cannot load OCI DLL: C:\oracle\product\10.2.0\db_2\BIN\oci.dll"

OS Windows Vista 64 bits sp2
Oracle 10g 10.0.2 - 64 bits Server

Toad for Oracle version 10.5.0.41 installed on the Database Server

I didn’t install the oracle client yet .

In your post you said :

Vista is no problem.
Toad can work with a 64 bit Oracle server,
but youhave to use a 32 bit Oracle client.

We won’t have the ability to use a 64 bit
client until our development environment (Delphi) has a 64 bit version ???

My Question is , based on my configuration above , why I am still getting the error msg ?

Is there a problem with 10.2 oracle client apparently

Toad works with a 10.2 client.
What is the exact error that you are getting?
Are you trying to use instant or normal client? (either should work)
32 or 64 bit? (it should be the same as Toad)
Do you have read and Execute permissions on the folder? (you should)

We work with Toad 12.7 and Oracle Client 10.2 normal. Both 32bit
Error: I have Cannot load OCI DLL c:\oracle\product\10.2.0\BIN\oci.dll (the file is present)
Already answered
I'm not sure, and that's my doubt: should I have read and execute permissions on the entire Oracle client path?

Thank you

If you have read and execute privileges on the files in the client\bin folder, that should be enough.

Do you have more than one oracle client installed?
If so, close Toad and restart it before trying to change from one Oracle client to the other. The DLLs don't always unload properly, and sometimes the different versions clash.

Do you have a product called DynaTrace installed? If so, that could be causing a conflict.

Thank you John, I will check the permissions part. And yes, we also have Oracle 11.2 32bit installed.
Dynatrace is not installed on my computer but i'll consider it for other cases that may have it installed

If you have and ORACLE_HOME environment variable set, remove or rename it.
Those should exist in the registry and no where else.

If you continue to have problems, this will probably solve it:

  1. delete both oracle clients.
  2. make sure the registry is clean - HKLM\SOFTWARE\Wow6432Node\Oracle is gone.
  3. make sure all traces of oracle client are gone off your hard drive
  4. reboot.
  5. reinstall the 10g client first and get it working
  6. Install the 11g client next.
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