Multiple greyed out buttons

This is a very common Excel + Teams/SharePoint scenario, and it’s almost never corruption.
The behavior you describe points to how the file is opened / protected, not grouping.

The #1 cause (by far): File is opened in Excel for the web / limited mode

When a file is stored in Teams, Excel often opens it in a mode where many commands are disabled, even if you have edit permissions.

Symptoms that match perfectly

• Many buttons greyed out across Home / Insert / Review
• Unprotect Sheet is disabled
• Happens even though you used to have full access
• File lives in a Teams channel

Fix

1. In Teams → click Open in Excel (not “Open”)
2. Or open the file directly from:
3. SharePoint → Open → Open in Desktop App
4. Make sure the title bar says:
5. Excel (Desktop)

Info: Excel for the web cannot unprotect sheets, even if you know the password.

Second most common cause: The workbook is protected, not the sheet

If Protect Workbook (Structure) is enabled:

• You cannot unprotect sheets
• Many buttons across the ribbon are disabled
• Sheets appear ungrouped → but structure is still locked

Check this

Go to:

Review → Protect Workbook

If it says Unprotect Workbook, click it and enter the password.

This is often set accidentally and forgotten.

Third cause: You are not the file owner

In Teams / SharePoint:

• You may have Edit permission
• But not be the original owner
• Some protections can only be removed by the owner

Check ownership

• Right-click file → Details
• Or check in SharePoint → Manage Access

If someone else owns it:
They must unprotect it once, then save.

Most likely fix (90% of cases)

Open the file in Excel Desktop and unprotect the workbook structure.

My answers are voluntary and without guarantee!

Hope this will help you.

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