To remove password protection from Excel, you need to open the spreadsheet and go to the File > Info section. Then, click on the Protect Workbook option and select the Encrypt with password option ...

If the Delete Sheet option is not working in Microsoft Excel and you are unable to remove a worksheet, use the following methods to fix the problem: Remove protection from your workbook.

Protected and unprotected cells look the same in a spreadsheet. To delete all unprotected cells, you must select all of them at once, which can be easily done by using the Find and Replace feature.