You will get more information about the problem in our knowledge base:
http://www.woltlab.com/help/?code=13011
Information:
error message: Unable to find parent 'option category' with name 'index' for category with name 'index.snowfall'.
php version: 5.2.17
wcf version: 1.1.9 (Tempest)
file: /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/acp/package/plugin/AbstractOptionPackageInstallationPlugin.class.php (84)
error code: 13011
date: 10/05/2012 10:35am
request: /acp/index.php?page=Package&step=OptionsPackageInstallationPlugin&queueID=305&action=install&packageID=48&s=08a2db5901cf1e38097bd5528e30b185ebf65371
referer:
http://www.rp-gamernetzwerk.de/acp/index…e30b185ebf65371
Stacktrace:
#0 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/acp/package/PackageInstallationQueue.class.php(146): AbstractOptionPackageInstallationPlugin->install()
#1 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/acp/package/PackageInstallation.class.php(32

: PackageInstallationQueue->executePackageInstallationPlugin('OptionsPackageI...')
#2 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/acp/package/PackageInstallation.class.php(52): PackageInstallation->install()
#3 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/acp/page/PackagePage.class.php(49): PackageInstallation->__construct(305)
#4 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/page/AbstractPage.class.php(46): PackagePage->show()
#5 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/util/RequestHandler.class.php(64): AbstractPage->__construct()
#6 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/wcf/lib/util/RequestHandler.class.php(92): RequestHandler->__construct('Package', Array, 'page')
#7 /homepages/30/d349843637/htdocs/rp-gamernetzwerk/acp/index.php(

: RequestHandler::handle(Array)
#8 {main}
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