I received a .shp polygon file. When I choose the edit toggle tool in QGIS the little red X's appear as expected. Then when I try to edit the polygons such as add a polygon all seems to go well, when finishing with a new polygon the dialog box for the attributes appears which allows entries and then upon closing the new polygon disappears. Also when trying to use the node tool it looks like a node can be moved but not really. Or any other editing such as editing the attribute by selecting a polygon with the information tool, the usual table appears and not the dialog table which allows entries into the attribute variables for the selected polygon. The file is not read only, other files are in the same directory which are editable. Any ideas what the difficulty is?