Issues with connection to Oracle Database data source in Power BI Desktop RS May 2026

[Andrikano]

There are two issues revealed in May 2026 version of Power BI Desktop RS app when working with "Oracle Database" data source.

[1] From May 2026 version Power BI Desktop RS cannot connect to TNS names from tnsnames.ora that linked using instruction "IFILE" (include from external file):

IFILE = N:\DBA\Oracle\additional_tnsnames.ora

January 2026 version can work with such external TNS names (although Report Builder never can).

[2] From May 2026 verson Power BI Desktop RS cannot connect to some usual TNS names that worked before. It returns strange Oracle error "Oracle: ORA-01017: invalid username/password; logon denied". But in fact credentials are correct, server is available. You can rollback Power BI Desktop RS to January 2026 version and same connection works again.

Problems above looks like some new bug in "Oracle Database" data source type.

[v-kathullac]

Hi @Andrikano ,

Thank you for reaching out to Microsoft Fabric Community Forum.

Could you please confirm if you are still facing the same issue? If so, could you briefly explain the issue, including the exact behavior and any error messages? This will help us investigate it further and get back to you with the appropriate solution.

Thanks,

Chaithanya.

[v-kathullac]

Hi @Andrikano ,
 

Thank you for posting your query in the Microsoft Fabric Community Forum.
 

Could you please confirm if your issue has been resolved using the suggested approach? This will help other community members facing similar scenarios.
 

Thank you .

[Andrikano]

There were no proposals here to solve the problems described.

[v-kathullac]

Hi @Andrikano ,
 

Thank you for posting your query in the Microsoft Fabric Community Forum.
 

Could you please confirm if your issue has been resolved using the suggested approach? This will help other community members facing similar scenarios.
 

Thank you .

[v-anbandari]

Hi @Andrikano ,
 

Thank you for posting your query in the Microsoft Fabric Community Forum.
 

Could you please confirm if your issue has been resolved using the suggested approach? This will help other community members facing similar scenarios.
 

Thank you .

[Andrikano]

No, it's wrong assumption. When IFILE is used in tnsnames.ora, Power BI Desktop RS May 2026 gives connection error. But when IFILE replaced with actual TNS descriptions, it gives "ORA-01017 (invalid username/password)" error. Only rollback to January 2026 version completely resolves these issues.

[Natalie_iTalent]

Hello @Andrikano,

The response you are referring has been removed due to inaccuracy.  Thank you for responding and communicating the inaccuracies.

Best, 

Natalie H.

Community Manager

[trivedisunita]

Hi @Andrikano 

Based on your testing, this does look like version-specific behavior. Since the rollback resolves issue, it’s likely something changed in the May 2026 build. Though I would avoid classifying it as a confirmed connector bug without Microsoft validation.

Note:  Drafted with AI assistance and reviewed before posting.