Unable to refresh semantic model after publishing in PowerBI

[Neha_Power]

Data source error: {"error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","pbi.error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","parameters":{},"details":[{"code":"DM_ErrorDetailNameCode_UnderlyingErrorCode","detail":{"type":1,"value":"-2147467259"}},{"code":"DM_ErrorDetailNameCode_UnderlyingErrorMessage","detail":{"type":1,"value":"We reached the end of the buffer."}},{"code":"DM_ErrorDetailNameCode_UnderlyingHResult","detail":{"type":1,"value":"-2147467259"}},{"code":"Microsoft.Data.Mashup.ValueError.Reason","detail":{"type":1,"value":"DataFormat.Error"}}],"exceptionCulprit":1}}} Table: CUSTOMER_SHIPTO.
Cluster URI: WABI-US-NORTH-CENTRAL-redirect.analysis.windows.net
Activity ID: 1474e0ae-52eb-4adb-9cf6-a299c55348c0
Request ID: 5cd9766b-6a98-4c94-97e2-1806ec0ab618
Time: 2025-04-10 02:03:09Z

[Poojara_D12]

Hi @Neha_Power 

The error "We reached the end of the buffer" along with DataFormat.Error in Power BI typically indicates a problem while reading or parsing data from the source, especially when the source returns unexpected or malformed data, or when the volume of data exceeds what the Power BI gateway or engine can process in one go. Since this issue is pointing to the CUSTOMER_SHIPTO table, it's likely that one or more rows contain data that's corrupt, improperly formatted, or too large.

To troubleshoot this, start by isolating the CUSTOMER_SHIPTO query in Power BI Desktop and attempt a refresh—this may highlight the specific step where the issue arises. Look for any binary columns, nested tables, or large text fields, especially ones that may be pulling inconsistent or null values. Also consider applying filters to reduce the data volume or splitting the data pull (e.g., by date or region). If you're accessing the data via an on-premises data gateway, check the gateway logs and make sure it's updated and has enough memory. Lastly, check the source system for changes—like schema alterations, nulls where values are expected, or special characters—that might affect parsing. Applying defensive logic in Power Query (like try...otherwise or type checks) can also help bypass bad rows and pinpoint the problematic

[Neha_Power · Accepted solution]

Hi all, Thanks for your responses. Resolved the issue by changing privacy settling of my connection to organization for all datasources through gateway.

[v-sgandrathi]

Hi @Neha_Power,

I'm glad you found a solution and resloved  the query. Thank you very much for sharing here.

Kindly mark your reply as the accepted solution so that others in the community can find it quickly.

Thankyou for connecting with Microsoft Community Forum.

[v-sgandrathi]

Hi  @Neha_Power 

We wanted to follow up since we haven't heard back from you regarding our last response. We hope your issue has been resolved.

If my answer resolved your query, please mark it as "Accept Answer" and give Kudos if it was helpful.

If you need any further assistance, feel free to reach out.

Thank you for being a valued member of the Microsoft Fabric Community Forum!

[rohit1991]

Hi @Neha_Power

I have also faced this issue few times where everything works fine in Desktop, but the moment it's published, the refresh fails in the Service usually throwing some gateway or credentials error.

A mismatch in the privacy settings (especially when combining different sources), or Power BI not being able to bind the dataset properly through the gateway even if the credentials test passes.

Sometimes, just republishing after clearing the permissions or reconfiguring the data source in the gateway helps too.

[v-sgandrathi]

Hi @Neha_Power,

Thank you for bringing this issue to the community.

 The error you're encountering, DM_GWPipeline_Gateway_MashupDataAccessError, with the underlying message “We reached the end of the buffer,” indicates a data formatting issue during the refresh of your semantic model in Power BI Service. This error is associated with the CUSTOMER_SHIPTO table and often occurs when the data source contains malformed or incomplete rows, or when a transformation applied through Power Query results in unexpected structure or data format.

To resolve this:
we recommend opening the PBIX file in Power BI Desktop and inspecting the CUSTOMER_SHIPTO query step-by-step in Power Query Editor. Look for any DataFormat.Error or transformation step that may be breaking due to bad data. You may also consider implementing error-handling logic using the try ... otherwise expression to gracefully skip problematic rows.

Review the original data source directly to check for any inconsistencies or malformed records. If the refresh fails in Desktop as well, that confirms the issue lies in the mashup logic or data structure itself. Once resolved, re-publish the updated report to the Power BI Service and test the refresh again. If you are using an On-Premises Gateway, ensure it is configured correctly and is able to access the source.

Thanks for reaching out! If this answer was helpful, please consider marking it as Accepted Solution and giving a Kudos, it helps the community!

Regards,
Sahasra.

[Neha_Power]

Hi Sahasra,

Thanks for your response. Issue is it gives different tables when I do manual refresh and I dont see any bad data in any of the tables and refresh works perfectly fine on desktop.

If it helps I am using Power Platforms dataflow as source while creating dashboard from PowerBI desktop.

Thanks,

Neha

[v-sgandrathi]

Hi @Neha_Power,

Since the refresh works fine in Power BI Desktop but fails with different tables during refresh in Power BI Service, it indicates that the issue is not with the data itself but with the Service-side connection to the source.

As you are using Power Platform Dataflows as the data source, the problem is likely related to factors like dataflow refresh timing, network instability, API throttling, or large data volume causing timeouts ("end of buffer" errors).

It is recommended to ensure that the Dataflow refresh is fully completed before the dataset refresh is triggered. You can manually refresh the Dataflow first and then refresh the dataset to check if it resolves the issue.

Also, consider optimizing large tables if possible. If the issue continues apart from these steps, it may be necessary to raise a support ticket with Microsoft, as intermittent refresh failures with Dataflows in Power BI Service can sometimes result from backend service limitations.

If my response was helpful, consider clicking "Accept as Solution" and give us "Kudos" so that other community members can find it easily. Let me know if you need any more assistance!

Thank you.

[v-sgandrathi]

Hi @Neha_Power,

May I ask if you have gotten this issue resolved?

If it is solved, please mark the helpful reply or share your solution and accept it as solution, it will be helpful for other members of the community who have similar problems as yours to solve it faster.

Thank you.