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There is an error. Please report the message (Piwik 2.9.1) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).
Notice: Undefined variable: idSite in /mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/plugins/BotTracker/API.php on line 127
Backtrace -->
#0 Piwik\Error::errorHandler(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/plugins/BotTracker/API.php:127]
#1 Piwik\Plugins\BotTracker\API::getBotByName(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/plugins/BotTracker/Controller.php:259]
#2 Piwik\Plugins\BotTracker\Controller->config_insert_db(…) called at [:]
#3 call_user_func_array(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/core/FrontController.php:582]
#4 Piwik\FrontController->doDispatch(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/core/FrontController.php:96]
#5 Piwik\FrontController->dispatch(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/core/dispatch.php:36]
#6 require_once(…) called at [/mnt/data/vhosts/casite-638320.cloudaccess.net/httpdocs/index.php:46]