I have 5 .shp files, after merge it with geomerge, I can't use it on OpenLayers with GeoServer. it's only show white layer and when i click it, it show error message: Internal error occurred ShapeType changed illegally from Arc to Point . what should I do?
The shapefile specification does not allow you to mix different types of shape in a single shapefile.
I've never heard of geomerge but it probably shouldn't allow you to do that as the end file won't be usable.
If you need all five files in a single WMS layer for some reason then look at layergroups instead.