I have a Windows 7 endpoint with 11.0.6200.754 and Office 2010. Certain Excel files on Server 2003 network shares display this error
“Unexpected file lock by (username). You can override this file lock, or continue without doing so. If you continue without overriding this lock, you will not be able to save the file, but you can use File Save As to save your work to a different file. Do you want to override this lock?”
Additionally we use folder redirection and a few files are locked specifically iTunes releated files in the same users My Documents folder.