diff --git a/src/external/u3d/src/IDTF/Converter.cpp b/src/external/u3d/src/IDTF/Converter.cpp
index bb8320a3d..72c829897 100644
--- a/src/external/u3d/src/IDTF/Converter.cpp
+++ b/src/external/u3d/src/IDTF/Converter.cpp
@@ -67,6 +67,7 @@ namespace IDTFConverter {
 bool IDTFToU3d(
 		const std::string& inputFileName,
 		const std::string& outputFileName,
+		int& resCode,
 		int positionQuality)
 {
 	const char* argv[] = {
@@ -220,6 +221,7 @@ bool IDTFToU3d(
 
 	IFXDEBUG_SHUTDOWN();
 
+	resCode = result;
 	return result == IFX_OK;
 }
 
diff --git a/src/external/u3d/src/IDTF/Converter.h b/src/external/u3d/src/IDTF/Converter.h
index 90e0c0a53..887176d44 100644
--- a/src/external/u3d/src/IDTF/Converter.h
+++ b/src/external/u3d/src/IDTF/Converter.h
@@ -22,9 +22,9 @@
 
 namespace IDTFConverter {
 
-bool IDTFToU3d(
-		const std::string &inputFileName,
+bool IDTFToU3d(const std::string &inputFileName,
 		const std::string &outputFileName,
+		int &resCode,
 		int positionQuality = 500);
 
 }
diff --git a/src/meshlabplugins/io_u3d/io_u3d.cpp b/src/meshlabplugins/io_u3d/io_u3d.cpp
index 026c361c9..1dd209303 100644
--- a/src/meshlabplugins/io_u3d/io_u3d.cpp
+++ b/src/meshlabplugins/io_u3d/io_u3d.cpp
@@ -111,13 +111,11 @@ bool U3DIOPlugin::save(
 		vcg::tri::io::ExporterIDTF<CMeshO>::Save(m.cm,qPrintable(tmp),mask);
 
 		//conversion from idtf to u3d
-		bool result = IDTFConverter::IDTFToU3d(tmp.toStdString(), filename, _param.positionQuality);
+		int resCode = 0;
+		bool result = IDTFConverter::IDTFToU3d(tmp.toStdString(), filename, resCode, _param.positionQuality);
 
 		if(result==false) {
-			QMessageBox::warning(
-						parent, 
-						tr("Saving Error"), 
-						errorMsgFormat.arg(fileName, vcg::tri::io::ExporterU3D<CMeshO>::ErrorMsg(!result)));
+			errorMessage = "Error saving " + QString::fromStdString(filename) + ": \n" + vcg::tri::io::ExporterU3D<CMeshO>::ErrorMsg(resCode) + " (" + QString::number(resCode) + ")";
 			return false;
 		}