TUFLOW Message 2226
ERROR 2226 - Multiple region objects not supported for Read MI Shape commands.
Multiple region objects, that is distinct polygons that are combined into a single geometry part, are not allowed. This error commonly occurs when there are holes in the polygon (negative spaces within a region). Note: this error is not referring to multi-part features, but rather multiple rings within a single part (i.e. a hole in the polygon).
Separate multiple region objects, this can be done in MapInfo, by selecting the object (it needs to be editable), and using selecting Objects >> Disaggregate. To remove negative spaces from regions select the object >> edit objects >> clean >> Gap Removal and set a minimum size greater than the negative space within the region.
A similar process can be done in QGIS to remove holes in polygons by using the 'Delete Holes' processing tool.