Error refreshing on desktop and service

[Iaguas]

My report stopped refreshing on desktop and service, displaying the following errors respectively:

"Failed to save modifications to the server. Error returned: 'OLE DB or ODBC error: [DataSource.Error] PostgreSQL: Exception while reading from stream.'"

and

Data source error: DataSource.Error: PostgreSQL: Exception while reading from stream. Microsoft.Data.Mashup.ErrorCode = 10478. DataSourceKind = PostgreSQL. DataSourcePath = iaguas. Message = Exception while reading from stream. ErrorCode = -2147467259. The exception was raised by the IDbCommand interface.
Cluster URI: WABI-BRAZIL-SOUTH-B-PRIMARY-redirect.analysis.windows.net
Activity ID: 2fc978bf-5030-459e-9f59-138f650ea91f
Request ID: 0f0b0bdc-e471-2848-66f9-0bb5f00aa0f9
Time: 2025-09-05 19:39:39Z

If anyone has experienced a similar error and can help me, I would appreciate it.

[v-menakakota]

Hi @Iaguas  , 

Thanks for reaching out to the Microsoft fabric community forum. 

This error usually happens when the connection between Power BI and PostgreSQL is interrupted. A few quick checks that often solve it:

• Make sure the PostgreSQL server is reachable and your network/firewall isn’t blocking the connection (whitelist the IP if needed).
• Update the PostgreSQL/Npgsql driver on both Desktop and the gateway.
• If you’re using a gateway in the Service, confirm it’s updated and connected.
• Try reducing the data being pulled (filter rows or simplify the query) to see if it refreshes.

If I misunderstand your needs or you still have problems on it, please feel free to let us know.   

 Best Regards, 
Community Support Team  

[v-menakakota]

Hi @Iaguas  ,

I hope the above details help you fix the issue. If you still have any questions or need more help, feel free to reach out. We’re always here to support you.

Best Regards, 
Community Support Team 

[v-menakakota]

Hi @Iaguas  ,

I hope the above details help you fix the issue. If you still have any questions or need more help, feel free to reach out. We’re always here to support you.

Best Regards, 
Community Support Team 

[AnkitaaMishra]

Hi @Iaguas ,

I faced the same error earlier. In my case, the issue was with network restrictions. Once I added my system’s IP address to the whitelist, the refresh started working fine. You may want to check if your network is blocking the request and whitelist the IP.

For Power BI Service, I’m using a gateway to handle the refresh, so make sure your gateway is updated and properly configured as well.

[Poojara_D12]

Hi @Iaguas 

The error you are seeing, “PostgreSQL: Exception while reading from stream”, usually points to an issue with the connection between Power BI and your PostgreSQL database, rather than with your report itself. This happens when the query engine starts receiving data from PostgreSQL but the connection is interrupted before completion. Common causes include network instability, timeouts due to long-running or heavy queries, resource limits being hit on the PostgreSQL server, or a mismatch in drivers. In Power BI Desktop, it often fails if the query is pulling back very large datasets without proper filtering, while in the Service it can also be affected by gateway configuration or idle connection timeouts. To fix it, you should check whether queries are optimized and returning only the necessary data, make sure the Npgsql/PostgreSQL ODBC driver is updated on both Desktop and the gateway machine, and confirm that the database server is not dropping long sessions due to memory, CPU, or timeout settings. If it works intermittently, it’s very likely network or gateway related; if it always fails at the same stage, it’s more likely a query or resource issue on the PostgreSQL side.

[NimaiAhluwalia]

Hello @Iaguas 

A list of possible solutions for you to try!!

• Confirm the PostgreSQL server is online and accessible.

• Verify credentials and permissions haven’t changed.

• Test the connection in Power BI Desktop → Data source settings → Test Connection.

• Ensure VPN, SSL, or firewall isn’t blocking Power BI.

• Large tables or queries returning huge datasets can cause streaming issues.

• Try filtering the data (e.g., limit rows to 1000) and see if it refreshes.

• Consider query folding or pre-aggregating data in the database before loading.

• Ensure the PostgreSQL ODBC/Npgsql driver is up-to-date on your machine.

• Power BI recommends using the latest Npgsql driver for PostgreSQL.

• Mismatched or old drivers can cause stream read errors.

• Increase the data load timeout in Options → Data Load → Timeouts.

• Temporarily disable background data to see if refresh succeeds.

• If using an on-premises gateway, check that the gateway version is latest.

• Ensure the gateway can connect to the PostgreSQL server.

• Check network stability interruptions can cause stream exceptions.

• Complex transformations in Power Query can break query folding.

• Review applied steps in Power Query and try simplifying transformations.

• Test if simpler queries refresh successfully.

• Enable diagnostic tracing in Power BI Desktop: File → Options → Diagnostics → Enable tracing.

• Split large tables into smaller chunks.

• Use incremental refresh instead of full refresh.

• Consider using DirectQuery mode instead of Import, if feasible