Thread:Project:Support desk/Fatal exception of type MWException after install MW from 1.21.0

1) Sorry for my broken englisch :-/

2) If I enable $wgShowExceptionDetails in LocalSettings.php, the following errors are display on the screen:

No cache directory configured

Backtrace:


 * 1) 0 /homepages/24/d450278213/htdocs/lumysearch/extensions/LocalisationUpdate/LocalisationUpdate.class.php(553): LocalisationUpdate::filename('de')
 * 2) 1 /homepages/24/d450278213/htdocs/lumysearch/extensions/LocalisationUpdate/LocalisationUpdate.class.php(36): LocalisationUpdate::readFile('de')
 * 3) 2 [internal function]: LocalisationUpdate::onRecache(Object(LocalisationCache), 'de', Array)
 * 4) 3 /homepages/24/d450278213/htdocs/lumysearch/includes/Hooks.php(255): call_user_func_array('LocalisationUpd...', Array)
 * 5) 4 /homepages/24/d450278213/htdocs/lumysearch/includes/GlobalFunctions.php(3883): Hooks::run('LocalisationCac...', Array)
 * 6) 5 /homepages/24/d450278213/htdocs/lumysearch/includes/cache/LocalisationCache.php(796): wfRunHooks('LocalisationCac...', Array)
 * 7) 6 /homepages/24/d450278213/htdocs/lumysearch/includes/cache/LocalisationCache.php(426): LocalisationCache->recache('de')
 * 8) 7 /homepages/24/d450278213/htdocs/lumysearch/includes/cache/LocalisationCache.php(310): LocalisationCache->initLanguage('de')
 * 9) 8 /homepages/24/d450278213/htdocs/lumysearch/includes/cache/LocalisationCache.php(245): LocalisationCache->loadItem('de', 'fallback')
 * 10) 9 /homepages/24/d450278213/htdocs/lumysearch/languages/Language.php(3978): LocalisationCache->getItem('de', 'fallback')
 * 11) 10 /homepages/24/d450278213/htdocs/lumysearch/languages/Language.php(230): Language::getFallbacksFor('de')
 * 12) 11 /homepages/24/d450278213/htdocs/lumysearch/languages/Language.php(189): Language::newFromCode('de')
 * 13) 12 /homepages/24/d450278213/htdocs/lumysearch/includes/Setup.php(497): Language::factory('de')
 * 14) 13 /homepages/24/d450278213/htdocs/lumysearch/includes/WebStart.php(161): require_once('/homepages/24/d...')
 * 15) 14 /homepages/24/d450278213/htdocs/lumysearch/index.php(55): require('/homepages/24/d...')
 * 16) 15 {main}

what should i do now?

thank you for youre help :-)