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Unhandled Exception at startup - Cannot load OCI DLL:


OK man am i tired of this issues.

I uninstalled everything, Oracle and SQL Nav 6.2.1

I have XP 64bit

I installed Oracle 11g
then i INstalled SQL Nav 6.2.1 and get this error. I installed SQL Nav in c:\questsoftware\ directory.

Our server is running Oracle 10G
My box is 64Bit Windows XP

All i want is Oracle Client and SQL Nav. My other XP 32 bit box works great with 10g client and Regular SQL Nav.

I have been fooling with this for a month now. I would really like to use my 64bit box.

can any please help.

My email is

thanks so much for your kind responses.



Hi Jeff,

This error can happen when there’s no client or the client was not setup correctly. Can you use SQLPlus to connect to any database? Do you have another tool such as an earlier version of sqlnav, toad to try out? Have you checked the Oracle path to see if it points to the right folder?



Please be aware that we don’t support 64 but client yet so please make sure you install 32 bit client instead.

Hope this helps,



I am using windows 7 64 bits with oracle developer suite installed (so its a 32bits)
and the workaround in
was needed for SQL Navigator to communicate with the DB.


Jeff mentioned that he installed sqlnav in C:\questsoftware\directory so he shouldn’t have the same issue you did.


Ola F Silva provavelmente é brasileiro. Vc poderia me falar qual a solucao para esse problema? Estou com o Vista 64bits Oracle 10 para vista 64 e Sql Navigator 6.2
Ele abre ja com essa mensagem de erro.
Tem alguma solucao que me indica?
Desde ja obrigado


Olá Marcelo, sou Português. O SQL Navigator actualmente somente funciona com o cliente 32 bits (o windows pode ser 64 bits). Ou seja se tem a Bd em 64 necessita de instalar também um cliente 32 bits para o SQL navigator utilizar (e outros programas a 32 bits).

Hi Marcelo. I’m Portuguese. SQL Navigator only works with 32 bits client (the windows system can be 64 bits). that means that if you have a 64 bits oracle installation in the same machine you still need to install a 32 bits client.
Message was edited by: Fsilva


Tudo bem Marcelo?
Estou como mesmo problema. Deu certo a instalacao do client 32 bits ? Ele instala no program files(x86)? Poderia me ajudar? meu email:
obrigado. abc Majela


Majela Fortes said:

"(…)I have the same problem. Did the 32 client install worked? Does it installs in program files(x86)? (…)

You can install the 32 bits client in that or in another path (I, for instance, have it in c:\oracle\client )

Majela podes instalar noutra pasta (eu, por exemplo, tenho em c:\oracle\client )


ReInstall your ’ OracleXEClient '

Sometimes this file goes corrupted … so you need to do it.