diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -11,6 +11,7 @@
     security.cpp
     tagsfilterchecker.cpp
     xmlloader.cpp
+    errorcode.cpp
 
     # A system by which queries can be passed to the user, and responses
     # gathered, depending on implementation. See question.h for details.
diff --git a/src/core/errorcode.h b/src/core/errorcode.h
--- a/src/core/errorcode.h
+++ b/src/core/errorcode.h
@@ -20,7 +20,12 @@
 #ifndef KNSCORE_ERRORCODE_H
 #define KNSCORE_ERRORCODE_H
 
-namespace KNSCore {
+#include "knewstuffcore_export.h"
+#include <qobjectdefs.h>
+
+namespace KNSCore
+{
+    KNEWSTUFFCORE_EXPORT Q_NAMESPACE
     /**
      * An enumeration of specific error conditions which might occur and which
      * users of KNewStuff would want to react to. It is used by both the Engine and
@@ -36,5 +41,6 @@
         InstallationError, ///< Installation of a content item has failed
         ImageError ///< Loading an image has failed. The entry name and preview type which failed will be held in the metadata as a QVariantList
     };
+    Q_ENUM_NS(ErrorCode);
 }
 #endif//KNSCORE_ERRORCODE_H