If this only happens in one particular document, try opening that
document and clicking on Tools | Unprotect Document.
If all new and existing documents are locked for editing, then
it's probably either because you have not activated your
Word/Office software, or because you have an expired trial
version of Office 2003. What happens if you start Word and click
on Help | Activate Product? If you are already activated, a
dialog box saying so will appear. If you are not activated, the
Activation Wizard will start. If you have an expired trial
version, a dialog box will prompt you to enter a valid product
key or purchase a key online.
