Known Issue: Databricks JDBC Reader OAuth Fails to connect to server in FME 2026.1

Issue

Databricks (JDBC) Reader database connection using the Azure OAuth - Client Credentials grant flow can fail with the following errors:

Failed to connect to server : https://xyz123.azuredatabricks.net:443
oauth-m2m auth: Failed to refresh credentials: invalid_client

Users on FME 2026.1 may encounter this issue with:

• A database connection that worked in older versions of FME
• A newly created database connection, using the default method (not specifying the JDBC database connection, see Workaround section below for details)
• Working OAuth Client details that successfully pass the web connection test in FME Form

Workaround

1. Upgrade FME

Use FME 2026.2 - Build 26307+ 

2. Specify JDBC Connection String

Specifying the database connection details manually, using “Advanced - Specify JDBC Connection String.”

Here is a guideline: 

1. In FME Options>Database Connections, add a new Databricks (JDBC) database connection. Scroll down to the Advanced - Specify JDBC Connection then enable it to expand the configuration details.
2. In the connection properties table, remove the existing lines for userAgentEntry, UID, and Password. Then add a new property: OAuth2Secret.
3. Click the ... button next to “Connection String” to open the Text Editor. Paste the following, replacing the placeholders in the angle brackets with your actual values:

jdbc:databricks://<server-hostname>:443;SSL=1;AuthMech=11;Auth_Flow=1;OAuth2ClientId=<your-azure-client-id>;AzureTenantId=<your-azure-tenant-id>

4. Fill in the connection properties table with your actual values for httpPath, connCatalog (your desired catalog name), and OAuth2Secret (your Azure client secret).
5. Optionally, enable “Mask Connection Details” to prevent sensitive details from appearing in plain text in your FME logs.
6. Click Test to verify FME can reach the server, then save the database connection before reading a table into FME, to confirm the connection is set up correctly.

Your connection should look similar to this:

Other configurations may still work. The steps above should serve as a guideline.

Resolution

This issue is currently unresolved. Please use the workarounds detailed above.

Support

If you have questions or need assistance with the workaround, please contact Safe Software Support.