--- a/Preferences/ConfigurationPages/EditorAPIsPage.py	Tue Nov 19 20:00:01 2013 +0100
+++ b/Preferences/ConfigurationPages/EditorAPIsPage.py	Wed Nov 20 18:45:58 2013 +0100
@@ -104,7 +104,7 @@
             self.__currentAPI.apiPreparationStarted.connect(
                 self.__apiPreparationStarted)
             self.addInstalledApiFileButton.setEnabled(
-                self.__currentAPI.installedAPIFiles() != "")
+                len(self.__currentAPI.installedAPIFiles()) > 0)
         else:
             self.addInstalledApiFileButton.setEnabled(False)