odbc interface working on Desktop but not on-premise

[Hansolu]

Hi

I do have a report server. On this server I do have a odbc connector installed, 64 bit version.

This connector is used for some older oracle DB but as well as for some SQL connection.  On the same server I installed the on-premise data gateway and connected several dataflows to grap and modify data.

Everything is up and running for months without issues.

Now, since last week, 3 of the odbc connections are not working anymore on the on-Premises. They still work if I start the desktop Powerbi version and connect to the source using these odbc.  

I did delete the gateway, installed the latest version (3000.278.5) of the on-premise gateway and restored the gateway with the recovery key. No change.

The error message in the dataflow:

Error code: UnknownError
Connection error: Unknown error
Cluster URI: https://api.powerbi.com
Session ID: xxxx6-e89a-xxxx-b50d-yyyy
Request ID: yyyy-3a86-4fbe-yyyy-xxxx
Time: Mon Jul 28 2025 16:09:22 GMT+0800 (China Standard Time)
:
Server-BI01: The operation is timed out.

Edit:

another strange things, i used to have another server, Server_test, same config, same connector, same gateway. On this server the dataflow and connections are working. So the setup must be okay, just something screwed up and I do not know what

Any ideas why this is happening all of a sudden? Nothing changed to my knowledge, no firewall, no updates,.. since 23.July no update possible

thanks

[v-sshirivolu]

Hi @Hansolu 
I have reviewed the issue and recommend the following actions to resolve the ODBC connection timeout on the on-premises data gateway:

• Review the gateway logs to identify any errors or timeouts related to the data source connection.
• Test the network connectivity between the gateway and the database using tools like ping or telnet, and verify network requirements to ensure communication is allowed.
• Validate the ODBC configuration for correct connection strings and driver setup.
• Use a UDL test to check if the database is accessible from the gateway machine.
• Recreate the dataflow in Power BI, as sometimes re-creating it helps resolve hidden configuration issues (dataflows documentation).
• Reinstall or update the ODBC driver for SQL Server to ensure compatibility.
• Test the ODBC connection using PowerShell or external tools to capture more detailed error outputs (PowerShell connectivity test).
• Increase ODBC connection timeout settings as explained in this guidance to handle long-running queries.
• Check firewall rules and port configurations per this performance guide to ensure uninterrupted gateway communication.
• Monitor system resources like CPU and RAM usage on the gateway server to rule out local performance bottlenecks (performance tuning).
• Confirm that the gateway is properly registered and online with Power BI (gateway management steps).
• Check the current Power BI service status to rule out any ongoing Microsoft-side outages that might affect connectivity.
• Make sure the gateway is running the latest version to avoid known issues resolved in recent updates.
• Regularly apply the monthly gateway updates to maintain compatibility and performance.

[Hansolu]

Hi, thanks for the reply, 

I will try some of the points.

Just to clarify, the SQL ODBC are all working, in the Dataflow and on the desktop version.

What is not working on the dataflow is the ODBC Oracle DB connector, this one on the other side is only working on the desktop.

the odbc driver on the server is an old one, oracle ODBC Version 11.2.0.1.0, guess from 2007. Issue is the old DB Structure of oracle behind, cant use newer versions. 

Again, used this driver for over a year I guess with no issues on the dataflow. 

thanks

KLaus

[jaineshp]

Hi @Hansolu ,

I’m experiencing identical behavior—ODBC-based dataflows on my gateway started timing out unexpectedly while they still work fine via Power BI Desktop.

Based on similar cases, this often stems from gateway-level timeouts or proxy/firewall misconfigurations interrupting ODBC queries. Refresh via Desktop succeeds because the gateway layer isn’t involved.

What worked for me:

1. Verified and reset timeout settings in the dataflow queries (removing custom values where possible).

2. Configured the gateway's config files with correct proxy settings in Microsoft.Mashup.Container.NetFX45.exe.config.

3. Restarted the gateway service and monitored logs—no firewall ports had changed, but proxy was blocking traffic.

After applying these changes, manual and scheduled refreshes for the affected ODBC dataflows started working again.

✅ I’m confident this will resolve the issue for others facing similar behavior.
If this helps, please consider giving it a kudos and marking it as the accepted solution. 👍

[Hansolu]

Hi,

thanks, but some question.

what do you mean in point 1, remove custom values is possible? Which custom values?

One thing i forgot to mention, once i open the online PQ editor, the error or timeout is coming before any data is downloaded, meaning I can not reach the database at all.

thanks

[v-sshirivolu]

Hi @Hansolu ,

Thank you for clarifying.

Since the Oracle ODBC connector fails to connect in the online Power Query Editor (even before preview), this suggests a possible gateway-layer connectivity or proxy configuration issue instead of a query or timeout error.

Here are some suggestions:

Verify that the ODBC driver version (11.2.0.1.0) is still compatible with Power BI Dataflows via the gateway. Recent gateway updates might have introduced stricter requirements. See version details here:
Download ODBC driver for SQL Server

If ODBC works on Desktop but not in Dataflow, the problem is likely at the gateway or network layer, possibly due to firewall or proxy issues.
Refer to:
Service Gateway Network Requirements
Service Gateway Log Files (for debugging)

Test Oracle connectivity separately using a UDL file on the gateway machine to help identify any driver-level problems:
Test OLE DB connectivity using a UDL file

Restart the on-premises data gateway after reviewing configuration settings and ensure it’s updated to the latest version:
Manage and Update Gateway
Monthly Gateway Updates

[Hansolu]

Hi, 

thanks for the thoughts. 

The driver you mentioned is not working for me. The ODBC SQL connections are okay.

The issue are the ODBC Oracle connections. The oracle DB I need to access is a very old system, thats why my driver is also very old.  

The error is happening already in online Power Query Editor (even before preview), yes. 

We did not change any proxy or Firewall. I will try to dive deeper with some colleagues on this, not my area of knowledge. 

Thanks

[v-sshirivolu]

Hi @Hansolu ,

Thank you for providing the additional information.

Since you're using an older Oracle ODBC driver (v11.2.0.1.0), this may be causing compatibility issues with the Power BI Service. While the driver might still function with Power BI Desktop, the online Power Query Editor relies on the On-premises Data Gateway, which requires newer TLS and security protocols.

Because the error happens before data preview, it's likely that the gateway is unable to establish a secure connection with the Oracle server due to protocol mismatches.

You might consider the following options help you resolve your issue:

• Use a SQL staging layer to transfer data from Oracle, then connect Power BI to SQL Server using supported drivers.
• Consider creating a custom connector for your legacy Oracle environment.
• Check the gateway logs for any handshake or protocol errors.
• If no changes were made to proxy or firewall settings, the age of the driver could be the main issue.

Since your Oracle setup is quite old, ongoing compatibility may not be possible. If further help is needed, please submit a support ticket with microsoft using the following link:
How to create a Fabric and Power BI Support ticket - Power BI | Microsoft Learn 

Thank you.

[Hansolu · Accepted solution]

Hi, 

short update, we deleted the odbc connector on the server, re-installed same version, latest on-premise gateway and now it is working again.

Not sure what was the final fix but its working.

thanks for your help