Saves all document's changes and drop document's operation history. IFileDocument.FileName property must not be empty to successfully call this method. In particular, the Save method may not be called after the IFileDocument.New method. IFileDocument.SaveAs method always set the IFileDocument.FileName property, so you may call the Save method after the SaveAs method was once called for a document.
ForceBackup parameter is ignored (assumed to be FALSE) if the current object represents the NTFS alternate data stream, physical disk, volume, process virtual memory or physical memory.