Based on the information available, the Microsoft Graph API allows for a range of operations on Excel files, including reading and modifying data in Excel documents. However, it is important to note that if a worksheet is protected, certain operations may not be possible. The API includes features for range and worksheet protection, and it is likely that reading cells from a protected worksheet would be restricted. For more detailed information on the capabilities and limitations regarding protected worksheets, you can refer to the official Microsoft Graph documentation or explore the Excel API endpoints provided by the Graph API.
https://learn.microsoft.com/en-us/graph/api/worksheetprotection-protect?view=graph-rest-1.0
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