When a computer crashes with a Word Document open or if Micrsooft Word unexpectedly closed, the document that was open will sometimes trigger a The document is locked for editing by another user error when trying to open the effected document. Users in this condition should delete the document's owner file. You can do this by following a few simple steps:
1. Close Microsoft Word. You can double check that no instances of Microsoft Word are open by checking Task Manager. Look on the Processes tab and end any instances of winword.exe found on the list.
2. Open Windows Explorer and navigate to the folder that contains the offending document (e.g. My Documents). The owner file has the same name as the file itself except that it is prefixed with a tilde and a dollar sign (~$). For example, a Word document named Sunday.docx will have an owner file named ~$Sunday.docx. Right click on the owner file and choose Delete from the context menu.
The file Sunday.docx should open properly now.