Protect Workbook Structure Without Confusing Cell Permissions in ONLYOFFICE

Workbook structure protection and cell protection solve different problems. Use the former to keep the tab arrangement stable; use the separate editable-input protection guide when formulas must resist editing. Do not describe either as file encryption.

Prepare a disposable three-sheet report

Use a new local workbook with no private data and no existing sheet protection. Create and name three sheets before applying any restriction:

Sheet and cell	Enter
Inputs!A1:C1	Item, Quantity, Unit price
Inputs!A2:C2	Sample box, 4, 12.5
Summary!A2	Extended amount
Summary!B2	=Inputs!B2*Inputs!C2
Archive!A1	Practice only

The independently calculated amount is 50. Use the decimal separator required by your locale. Save a checkpoint such as structure-before.xlsx. Keep that unprotected checkpoint unchanged while testing a separate working copy.

Rename and arrange the tabs now, using the worksheet organization guide if needed. Hide Archive through its sheet-tab menu. Inputs and Summary should remain visible. The Archive label is harmless test content, not data that needs secrecy.

Apply a structure guard

The official workbook protection instructions describe restrictions on tab operations, including renaming, moving, adding, removing and changing visibility.

1. In the working copy, open Protection → Protect Workbook.
2. Leave the password empty for this reversible exercise, then choose Protect. The documented toolbar state indicates that the guard is active.
3. Record the visible tab names and order before attempting a harmless change.

A password-free guard can be removed by anyone. For a real workbook, follow its owner’s password policy; the vendor warns that a forgotten protection password cannot be recovered. This exercise neither sets nor stores a real password.

Test structure and content separately

First try to rename Summary to Summary test. Under the documented structure guard, this change should be unavailable or refused. Inspect the tabs: Summary must keep its original name. If the rename actually succeeds, undo it immediately, verify the original name, and stop to inspect the protection state rather than proceeding as if the guard worked. Do not test deletion on valuable sheets.

Next return to Inputs and change B2 from 4 to 5. This workbook deliberately has no sheet-level protection. Check Summary!B2 for 62.5. The key distinction is that a structure restriction is not a rule that freezes ordinary input cells. If the cell edit is blocked, check for sheet protection, read-only file access or another restriction instead of attributing it automatically to the structure guard. The protection overview separates these mechanisms.

Restore Inputs!B2 to 4 and verify 50 again. A successful return to the baseline matters: do not leave the demonstration’s changed quantity in the final report.

Inspect the sheet visibility commands without exposing real data. The documented structure guard should prevent unhiding Archive through the usual tab controls. That is a user-interface restriction, not evidence that its contents are encrypted or safely removed from the file.

Remove the guard and verify recovery

With this password-free copy, use Protect Workbook again to remove the guard. Rename Summary to Summary test, then back to Summary. Unhide Archive and confirm A1 still contains Practice only. Confirm the three tab names and the amount 50. These are reversible checks, not instructions to remove protection from someone else’s workbook.

For a retained practice copy, hide Archive again, reapply the password-free structure guard and save under a new name. Close and reopen that copy, then repeat the harmless rename and quantity checks. Record the actual result in your installed version; save/reopen persistence was not tested for this article. Keep the untouched checkpoint until those checks pass.

Diagnose the wrong kind of protection

• Cells remain editable: this is not itself a structure-protection failure. Use sheet/cell protection for the separate input-versus-formula requirement.
• The whole file cannot be opened: investigate file encryption, file permissions or corruption. The structure guard is not a password-to-open workflow.
• A toolbar control is absent: identify the edition, build and file permissions. Hosted integrations can expose a different permission surface; do not assume the local exercise proves web or mobile parity.
• Hidden content must be confidential: remove it from an authorized distribution copy or choose appropriate access/encryption controls. Hiding a tab and guarding its menu are not a confidentiality certification.

Scope and evidence

This is a documentation-qualified free ONLYOFFICE Desktop Editors 10.0.0 local-file exercise for the English Windows/Linux interface. The desktop overview describes the open-source local-file product; the desktop changelog dates 10.0.0 to October 13, 2026. The Protection tab reference includes desktop and online views, but that does not establish identical host permissions.

Arithmetic and the test sequence were checked independently. No native execution, screenshot, password recovery, encryption-strength test or export fidelity is claimed. Older builds, macOS, mobile and hosted collaboration are outside this walkthrough.