microsoft purview information protection doesn't support labelling for the current file format. the file might be an old office format

@Nelson Thomas

It looks like you're trying to apply Microsoft Purview Information Protection labels to a file, but you're getting the following error:

"Microsoft Purview Information Protection doesn't support labelling for the current file format. The file might be an old Office format."

This error usually means that the file you're working with is in an older Office format—for example, .doc, .xls, or .ppt instead of the newer formats like .docx, .xlsx, or .pptx. Microsoft Purview labels only work with modern Office file formats, and unfortunately, the older formats aren't supported for labeling.

Please try the following steps:

1. Open the file in the latest version of Microsoft Office (Word, Excel, or PowerPoint).
2. Go to File > Save As.
3. Save it in the modern format (e.g., .docx, .xlsx, or .pptx).
4. Reopen it in the Microsoft Purview Information Protection viewer and try again.

For more details refer: https://learn.microsoft.com/en-us/purview/sensitivity-labels-office-apps#office-file-types-supported

Hope this helps. Do let us know if you have any further queries.

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