File Format & Compatibility

Fix PowerPoint Open XML Validation Errors with Chart Data Labels

Maira Mehtab Sep 22, 2026 869 views

Question details

The user needs to resolve an Open XML validation failure in PowerPoint 365 where a clustered column chart with centered, formatted data labels triggers an unexpected showDLblsOverMax element error.

Product: PowerPoint 365
Device & OS: not provided
Scenario: Validating a PowerPoint presentation containing a clustered column chart against the Open XML schema.
Observed behavior: The Open XML validator reports an unexpected showDLblsOverMax element under the chart object, causing the presentation to fail validation.

Before you start

Before reaching out for support, ensure you have documented your exact PowerPoint build number, saved a copy of the validator output log, and isolated the error in a sample presentation.

Solution 1Recommended

Report the Schema Conformance Issue to Microsoft Support

Because this is a known schema-conformance bug originating within PowerPoint 365's XML generation, it requires an official product-team investigation rather than a local settings fix.

The showDLblsOverMax element error occurs because PowerPoint 365 writes an attribute to the XML structure that the standard Open XML validator does not expect. As this is a software-level bug, standard troubleshooting will not resolve it directly, and the issue must be escalated.

Document the reproduction steps

Write down the exact steps taken to create the clustered column chart and format the centered data labels, noting your current PowerPoint 365 build number.

Prepare a minimal sample presentation

Create a new, blank presentation containing only the specific chart that triggers the unexpected showDLblsOverMax element to share with the support team.

Open a Microsoft 365 support request

Ask your organization's Microsoft 365 administrator to navigate to the Microsoft 365 admin center and open an official support request at https://learn.microsoft.com/en-us/microsoft-365/admin/get-help-support.

Temporary Workaround: While waiting for Microsoft to release a fix, you can temporarily bypass the validation error by changing the data label position from 'Center' to 'Outside End' or by removing the specific label formatting.

Free Microsoft Office alternative

Use WPS Presentation for Seamless Chart Creation

If you are encountering persistent XML schema validation bugs in PowerPoint, consider switching to WPS Office. It provides a highly compatible and lightweight alternative for creating stunning presentations without triggering unexpected validation errors.

1. Download and Install WPS Office: Visit the official WPS website to download and install the free WPS Office suite on your device.
2. Open your Presentation: Launch WPS Presentation and click on 'Open' to load your existing .pptx file.
3. Edit Charts Without Errors: Modify your clustered column charts and data labels using the intuitive chart tools, then save your file seamlessly.

Highly compatible with Microsoft PowerPoint (.pptx) formats.Create and format clustered column charts effortlessly without schema errors.Free and lightweight with a highly familiar user interface.Avoid specific Microsoft 365 XML generation bugs.

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Frequently Asked Questions

What causes the unexpected showDLblsOverMax element error in PowerPoint?

This error is caused by a schema-conformance bug in PowerPoint 365. When you format data labels to appear in the center of a clustered column chart, the software writes an unexpected XML element that the standard Open XML validator rejects.

Can I manually fix this validation error in my file?

Because this is a bug in how PowerPoint 365 generates the XML code, there is no direct user setting to fix it. You must either wait for a product team update or use a workaround, such as changing the data label position away from the center.

Will this Open XML error prevent my presentation from opening?

Usually, the presentation will still open and display normally in PowerPoint. However, it will fail strict Open XML schema validation, which might cause issues with automated document processing systems, third-party software, or strict compliance checks.

How do I contact Microsoft to report this PowerPoint bug?

If you are part of an organization, your Microsoft 365 administrator can submit a detailed support request, including reproduction steps and the validator output, directly through the Microsoft 365 admin center's help and support portal.

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