Troubleshooting a linked server (error 7302 Could not create an instance of OLE DB provider ‘OraOleDB’)

I spent the last two days looking on internet for a solution on a linked server error know as ‘7302’, there are a lot of hits and the same 3 or 4 solutions keep coming up, I tried them all but no success. To save you from going through endless solutions I am going to sum up all the possible solutions, ending with the most valuable solution, well at least it was the best fix for me.

Here are links to linked server articles I wrote before:

building a linked server
Creating jobs and queries with linked server

Now, the dreading 7302 error Could not create an instance of OLE DB provider ‘OraOleDB’
First a solution that saved our asses last time, but this won’t always do the trick! “After installing a new service pack to the mssql server in 2011, the linked server stopped working, giving an 7302 error ‘Could not create an instance of OLE DB provider ‘MSDAORA’. If your LS stops working after it has been working fine for months and all the tips above are working, i found a quick work around to get your Linked server to work again, just simply check the dynamic parameter box and save and then uncheck it again.”

But this time we didn’t get away with it this easy, almost the same error, different solution needed

once again this error occurs after a series of windows updates we performed, so we started undoing the updates, but ofcourse the error stayed.

On the internet they advise you to change the DCOM security of the MSDAINITIALIZE (Acces Permissions was on Use default, change it to customize, if not already, change the other 2 in customize as well.)

I added the domain user to the permission section. But this solution didn’t work in my case. secondly we opened the Registry and look for: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\AppID\{2206CDB0-19C1-11D1-89E0-00C04FD7A829} and change the owner to administrator, but in my case administrator was already the owner, so no luck here. (source: http://blogs.msdn.com/b/dataaccesstechnologies/archive/2011/09/28/troubleshooting-cannot-create-an-instance-of-ole-db-provider.aspx)

I also checked the Environmental Variables to see if the PATH still contained oracle (e.g. D:/ORACLE/BIN;D:/Oracle/Client;)

Then i tried reconfiguring the Oracle ODAC install in cmd:

D:\oracle>configure
D:\oracle>configure all orahome

but still no luck…

Sometimes restoring your dll files from the day before the error occurs does the trick, but again..nothing.

So, my final solution, re-install the oracle client, this time, with a standard oracle tree that contains some tools to check network and database connection, tnsping and sqlplus.

(re)installing oracle environment:

i used two oracle installations

– Oracle Database 11g Release 2 Client (11.2.0.1.0) for Microsoft Windows x64 (64-bit) this installs the standard oracle home and tools like tnsping and sqlplus

– 64-bit ODAC 11.2 Release 5 (11.2.0.3.20) Xcopy for Windows x64
for a non heavy client for LS to depent on.

first install the oracle 11.2.0.1.0 client and tools.

edit the tns names ora file to your database:

Secondly we reinstalled the ODAC again, now the OraOleDB drivers are available again. Everything is configured for the LS again. MSSQL needs to reload the OraOLEDB file in, for it will keep the old, corrupt file in use, we need to restart the mssql servers.

So if you walked the same path like me, just reinstall oraclient environment. Good luck!

Special thanks to B. Kooiman for helping with the oracle install!

Creating a linked server Oracle to MsSQL and common Error 7302 Could not create an instance of OLE DB provider ‘MSDAORA’

n some cases it can be handy if you can query a database from one database server to the other and copy data and tables.

Now the fun part is, we can use this on different databases as well, like Oracle, MySql e.g. how cool is that!
Let’s set up a linked server to Oracle.
If you don’t have oracle available, you can download and install the Oracle Express edition, which we can get for free from the Oracle site.

In some cases it can be handy if you can query a database from one database server to the other and copy data and tables.

Now the fun part is, we can use this on different databases as well, like Oracle, MySql e.g. how cool is that!
Let’s set up a linked server to Oracle.
If you don’t have oracle available, you can download and install the Oracle Express edition, which we can get for free from the Oracle site.

After you have succesfully installed Oracle server, fire up MSSQL.

First we are going to create a new database for this Linked Server Project, let’s call it the ‘FunFactory’ a great program from the ’80.

Insert some tables and rows and we’re done! Now we open the Server Objects in the Object Explorer and right click ‘add new linked server’:

Now it’s very important to fill in the right credentials: You need to connect Oracle on it’s TNS name, for example, Oracle Express the default is XE, now press ‘script from’, to see the script that will execute when you press ok.

Ok, enought with the boring GUI, we are going to create another linked server, but this time we script it:

DECLARE @vcLinkedServer VARCHAR(255)
DECLARE @vcLocalUser VARCHAR(255)
DECLARE @vcRemoteUser VARCHAR(255)
DECLARE @vcRemotePass VARCHAR(255)
DECLARE @vcRemoteTNS VARCHAR(255)
DECLARE @ncStatement NVARCHAR(MAX)
SET @vcLinkedServer = 'FunFactory'
SET @vcLocalUser = SYSTEM_USER
SET @vcRemoteTNS ='XE'
SET @vcRemoteUser = 'Fun'
SET @vcRemotePass = 'Factory'
/*
SET @ncStatement = 'USE MASTER
GRANT ALTER ANY LINKED SERVER TO ' + SYSTEM_USER + '
USE ' + DB_NAME()
EXEC sp_ExecuteSQL @ncStatement
*/
BEGIN TRY
EXEC sp_DropServer @vcLinkedServer, 'droplogins'
END TRY
BEGIN CATCH
END CATCH
EXEC sp_AddLinkedServer @vcLinkedServer, 'Oracle', 'OraOLEDB.Oracle', @vcRemoteTNS
EXEC sp_AddLinkedSrvLogin @vcLinkedServer, 'FALSE', @vcLocalUser, @vcRemoteUser, @vcRemotePass
DECLARE @vcTableName VARCHAR(255)
DECLARE @vcFieldName VARCHAR(255)
DECLARE @vcFieldType VARCHAR(255)
DECLARE @vcColumnsDest VARCHAR(MAX)
DECLARE @vcColumnsSrc VARCHAR(MAX)
DECLARE @iIsNullable INT

That’s better! To check if both linked servers excist, we do a spfile check:

exec sp_helpserver

Great, this part seems to work!

Now we need to make sure we can establish a connection to Oracle
make sure Oracle is installed properly or it will result in some common errors:

Error 7302: Could not create an instance of OLE DB provider ‘MSDAORA’

There is 2 things you need to do here:

Check if provider oraOLEDB is available

And make sure ‘Allow In process’is checked in the provider options

 

If it still does not work:
Make sure correct OLEDB (and oracle client) are installed. If not, search for ODAC on the Oracle site.

http://www.oracle.com/technetwork/database/windows/downloads/index-090165.html

In our case SQL is on a 64 bit server, so we choose the ODAC x64 zip file
In order to get it installed, we need an ‘oracle way’ just running the install.bat won’t do the trick, or oracle wouldn’t be oracle 😉
We run the install from cmd or Powershell:

C:\Teletraan_I\Mellie>D:
D:\>cd ODAC112021_x64
D:\ODAC112021_x64>install
D:\ODAC112021_x64>install all d:\oracle orahome
D:\ODAC112021_x64>cd..
D:\>cd oracle
D:\oracle>configure
D:\oracle>configure all orahome

On last thing could stand in your way, a classic oraclient failure:
The path is not inserted in the environmental settings:
Go the PATH and add the location of the newly installed oracle home.

PATH:D:\oracle\bin;D:\oracle;

Now the Oracle dir is created on your computer and the linked server is airing, Hooray! It kinda feels like swearing in the Church, installing an oracle client on your SQL server, but what needs to be done….

You can now write queries to copy oracle tables over to your SQL server and what ever you want to do with data in a database!!! I absolutely love this Linked server thingy!

In my next Linked Server post, I will show you some cool stuff that you can do with data in Linked servers! note: here is the link: Creating jobs and queries with linked server

Note:
After installing a new service pack to the mssql server, the linked server stopped working, giving an 7302 error ‘Could not create an instance of OLE DB provider ‘MSDAORA’. If your LS stops working after it has been working fine for months and all the tips above are working, i found a quick work around to get your Linked server to work again, just simply check the dynamic parameter box and save and then uncheck it again. Weird but it does work!

If this quick fix does not do the trick, I wrote a more detailed troubleshoot on linked server here: Troubleshoot linked server