Please try to the following and see if it resolves your issue 1. Open the Windows Registry editor. 2. Navigate to HKEY_CURRENT_USER\Software\Mindjet\MindManager\17\Spelling Checker 3. Delete entry 'DictionaryFolder' 4. Re-start MindManager and observe if the error is still there. 5. If the error message is still displayed, please proceed to uninstall and then re-install MindManager 2017 latest through the Windows Control Panel.