Custom xml file having issue after installation an power point addin

The issue you're experiencing with the PowerPoint add-in seems to be related to the custom UI XML markup that you are using. The error message indicates that there is a mismatch between the specified control type (button) and the actual control type (toggle button) in your XML markup. This can cause the add-in not to load correctly.

To resolve this issue, you should:

1. Review your custom UI XML markup to ensure that the control types are correctly defined and match what is expected. Make sure that if you are using a toggle button, it is defined as such in your XML.
2. Check for any other errors in the XML markup that could prevent the add-in from loading. If there are any errors, they need to be corrected.
3. Enable error reporting in PowerPoint to get more detailed information about any issues with the add-in. You can do this by going to File > Options > Advanced, and under Developers, select Show add-in user interface errors.
4. If the issue persists, consider reinstalling the add-in after ensuring that the XML markup is correct and that there are no compatibility issues.

By following these steps, you should be able to troubleshoot and resolve the issue with your PowerPoint add-in.

References:

• Detecting Errors
• Show Add-in user interface errors

Hi @Ajay Kumar

Thank you for posting your question in Microsoft Q&A. 

Based on the information you provided, I understand you're encountering an issue with a custom PowerPoint Add-in on some user machines. The installation finishes very quickly (which is unusual), and after installation, the add-in doesn't appear in PowerPoint. You are seeing a specific XML error: "custom UI XML, the type of control specified is not compatible with the actual type of control having the ID of superscript toggle button."

The error message clearly indicates a mismatch in your add-in's Ribbon XML file. Specifically, you are trying to use the built-in control idMso="Superscript" (which is a toggle button in Office that turns superscript on/off), but you have defined it incorrectly in your XML.

Because Office detects this invalid XML structure, it refuses to load the add-in's UI, which explains why the add-in is "missing" from the ribbon. The unusually fast installation suggests the installer might be skipping steps or failing silently during registration due to this validation error. Please try the following steps to fix the XML mismatch:

1. Fix the Ribbon XML

If you intend to use the built-in Superscript functionality as a toggle:

Open your add-in's Ribbon XML file (e.g., Ribbon.xml or within your manifest) > Find the line referencing the Superscript control. It probably looks like this:

<button idMso="Superscript" ... />
Change it to:

<toggleButton idMso="Superscript" ... />

Keep other attributes (like label, imageMso) unless they are causing specific errors > Save, rebuild/repackage, and reinstall the add-in.

Note on Callbacks: If you are implementing custom logic for this button:

• You must provide a GetSuperscriptPressed(IRibbonControl control) callback that returns true/false (current state).
• You must provide an OnSuperscriptToggle(IRibbonControl control, bool pressed) callback to handle state changes.
• Make sure your callback names in the code match the XML declaration exactly.

2. Check Add-in Status & Installation

Since the installation was suspiciously fast, verify the add-in's state in PowerPoint:

Go to File > Options > Add-ins > Look for your add-in in the "Inactive", "Disabled", or "Document-related" lists > If it is disabled, select "Disabled Items" in the Manage box and click "Go..." to re-enable it > If it is not in the list at all, the installation failed to register it correctly.

3. Enable User Interface Errors

To see diagnostic details when the add-in loads > Go to File > Options > Advanced > General > Check the box "Show add-in user interface errors". This will confirm if the XML fix worked.

4. Check for Consistency

Since you mentioned the issue happens on some machines, ensure all machines have the same Office version and necessary dependencies installed. Also, if your add-in is a .ppam file, check the file properties on the problematic machines and ensure "Unblock" is checked if present.

I hope this information helps you resolve the issue!

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