I'm writing a VSTO-project for excel. The workbook has hidden tabs and fields
and is protected with a password. But I would like to enforce a stricter
security-policy: users should only be allowed to unprotect the sheet if they
are part of a specific group. If they're not in the group, they cannot
unprotect, even if they know the password.
I tried to find an event that fires when the user unprotects the sheet, but
no event I can hook into exists. I tried to override the unprotect-method,
but it seems impossible.
Is there any way I can add my security-implementation to the already present
built-in security ?