I have upgraded from version 7.0.6 to 7.1.0. Now I always get an error message when I try to create a new page.

Error message:
Fehler: ist zur Zeit nicht verfügbar. DotNetNuke.Services.Exceptions.ModuleLoadException: An item with the same key has already been added. ---> System.ArgumentException: An item with the same key has already been added. at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) at DotNetNuke.Entities.Modules.ModuleInfo.get_LocalizedModules() at DotNetNuke.Entities.Modules.ModuleController.LocalizeModule(ModuleInfo sourceModule, Locale locale) at DotNetNuke.Entities.Tabs.TabController.CreateLocalizedCopy(TabInfo originalTab, Locale locale) at DotNetNuke.Entities.Tabs.TabController.CreateLocalizedCopies(TabInfo originalTab) at DotNetNuke.Modules.Admin.Tabs.ManageTabs.SaveTabData(String strAction) at DotNetNuke.Modules.Admin.Tabs.ManageTabs.cmdUpdate_Click(Object Sender, EventArgs e) --- End of inner exception stack trace ---


Does anyone know what the problem is?