Dear @LIG_AB
The error message typically indicates that Word has detected corrupted content or a compatibility issue within the document. To help me identify the root cause, could you please answer the following questions:
- What troubleshooting steps have you tried before?
- Does the error occur for all users, or only specific users?
- If you create a brand-new template with the same content and controls, does the issue still occur?
- If you download the template locally and create a document outside of SharePoint/Google Workspace, does the problem persist?
According to my research, here are some troubleshooting steps I recommend you try:
Step 1: Repair the Word Document
- In Word, go to File > Open from the left sidebar. Then, click the Browse option. > select the file, click the dropdown next to Open, and choose Open and Repair. For more information, please refer to Open a document after a file corruption error

Step 2: Remove the Read-Only Attribute
- Right-click on the problematic Word file and select Properties > Under the General tab, clear the Read-only checkbox. Then, hit Apply, followed by OK.

Step 3: Restore an Earlier Version of the Word Document
If the Word document you are trying to access was saved to OneDrive, you can attempt to restore an earlier version of the document. This should help revert any changes that may have damaged the document.
- Press Windows + S to open the search menu, type OneDrive, and select Open > Locate the Word file you are trying to open > Right-click on it and select Show more options
- Select Version history from the list > Hover your mouse over an earlier version of the document on the list. Click the three-dot icon and select Restore.
- Note: You can also download the previous version of the file and see if Word can open it.

Step 4: Disable Protected View in Word
Open Microsoft Word and select Options from the left pane > Trust Center tab and click the Trust Center Settings button > Clear all three checkboxes to disable Protected View and click OK to save changes.

For references, you can refer to 5 Ways to Fix “Word Found Unreadable Content” Error and How to Fix Unreadable Content in Word: A Step-by-Step Guide
Disclaimer: *These link is shared by community members for your convenience. It points to a third-party site that is not managed or verified by Microsoft. We can’t guarantee the quality, safety, or suitability of any content or software found there. Please review carefully and make sure you understand any potential risks before using it.*I hope the information shared is helpful. Please follow these steps and let me know if it works for you.
If you have any questions, please feel free to reach out. I'm looking forward to your update.
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