Short answer
What you need to know
Unhide rows, columns, and worksheets; inspect Name Manager, formulas, comments, links, objects, and properties. A sheet marked very hidden may not appear in Excel's ordinary Unhide dialog and requires deeper inspection.
What a workbook can hide
Excel supports hidden rows, columns, and worksheets. Workbooks can also retain very hidden sheets, defined names, formulas, comments, external links, cached values, properties, and embedded objects.
Templates and calculation models often use these features legitimately.
Manual workbook review
Work on a duplicate, select the entire sheet, and use the row and column Unhide commands.
Unhide worksheets, inspect Name Manager, show formulas, review comments, notes, links, data connections, and objects outside the visible area.
For high-stakes review, use a trusted tool that reports very hidden sheets.
How the scanner helps
Hidden Word Scanner reports hidden and very hidden worksheets, concealed rows and columns, formulas, defined names, comments, links, properties, and embedded objects in supported XLSX workbooks.
Important limitation
Verify important findings
Encrypted files, macros, external data sources, legacy XLS files, and add-ins may require dedicated analysis. Evaluate findings in the workbook's real context.
Further reading
Authoritative references
These primary sources support the manual steps in this guide. Their inclusion does not imply endorsement of Hidden Word Scanner.