The sandbox:/mnt/data/ path indicates that the file is stored inside a temporary sandbox environment, not in a normal local or cloud folder. To get back to the presentation, it must be opened or saved from a location that the app can access outside that sandbox.
Use one of these approaches, depending on how the file was originally saved:
- If the presentation is still open in the app
- Use File > Save As (or equivalent) and choose a regular location such as Documents, Desktop, or a cloud location like OneDrive.
- After saving, open it from that new location instead of the
sandbox:/mnt/data/path.
- If the file was downloaded in a browser-based sandbox
- Look for a Download, Export, or Save a copy option in the web experience and choose a normal folder (for example, the system Downloads folder or OneDrive).
- Then open the file from that folder in PowerPoint or the relevant app.
- If using PowerPoint on macOS and hitting sandbox-related prompts
- Move or save the presentation to OneDrive and open it from there so the app can access it without extra prompts.
- Alternatively, store it inside the PowerPoint sandbox folder at
~/Library/Containers/com.microsoft.Powerpoint/Data/Documents/and open it from there.
Once the file is saved to a non-sandbox path (local folder or OneDrive), the sandbox:/mnt/data/ reference is no longer needed; always open the presentation from the new saved location.
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