Hi Arndt, this one is not so obvious to me. Please can you post the complete error message, esp. the line with AssertionError ? Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von Arndt Röhrig <arndt@speichenkarte.de> Gesendet: Mittwoch, 25. April 2018 15:27:30 An: Development list for mkgmap Betreff: [mkgmap-dev] mkgmap4176 java-error Hi @all mkgmap4176 failed to build a map from Bayern. (aftes building all tiles) 4165 works well. Maybe a similar problem like yesterday? Or some exotic types in my style? FileWriter.java:213) at uk.me.parabola.imgfmt.app.mdr.Mdr29.writeSectData(Mdr29.java:96) at uk.me.parabola.imgfmt.app.mdr.MDRFile.writeSection(MDRFile.java:421) at uk.me.parabola.imgfmt.app.mdr.MDRFile.writeSections(MDRFile.java:385) at uk.me.parabola.imgfmt.app.mdr.MDRFile.write(MDRFile.java:269) at uk.me.parabola.mkgmap.combiners.MdrBuilder.onFinishForDevice(MdrBuild er.java:355) at uk.me.parabola.mkgmap.combiners.GmapsuppBuilder.onFinish(GmapsuppBuil der.java:178) at uk.me.parabola.mkgmap.main.Main.endOptions(Main.java:678) at uk.me.parabola.mkgmap.CommandArgsReader.readArgs(CommandArgsReader.ja va:128) at uk.me.parabola.mkgmap.main.Main.mainStart(Main.java:143) at uk.me.parabola.mkgmap.main.Main.main(Main.java:114) Greetz Arndt