Windows 7 and 8.1. LibreOffice (was OpenOffice) 188.8.131.52. Having files open, working. Had hoped they'd be synced to laptop so I can leave with laptop and keep working. Fails with "1 locked file". If _lucky_ can save (must have a change) and quickly quit LibreOffice and then it syncs. If not lucky, fails because still locked, and won't try until next folder_rescan_interval, way too late. That is not a way to live. Would need a higher degree of certainty. Nothing is totally certain in life, but this is very painful. Made it more bearable by setting folder_rescan_interval to 60 (instead of default 600). I see two (only one good) possible solutions: 1) Sync could use Volume Snapshot Service (if you think that should be optional per folder so be it). That would be the ideal solution. These LibreOffice files are good, even though they're locked while open in LibreOffice. 2) Sync could be notified when the file becomes unlocked (that is less desirable, but still better than current), if that is possible, not sure whether that is a notifiable attribute.