Importer issues

PHP warning in file /home/nginx/domains/servinglinux.com/public/wcf/lib/system/importer/UserImporter.class.php (144): strlen() expects parameter 1 to be string, array given




Stacktrace:
#0 [internal function]: wcf\system\WCF::handleError(2, 'strlen() expect...', '/home/nginx/dom...', 144, Array)
#1 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/importer/UserImporter.class.php(144): strlen(Array)
#2 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/exporter/XF12xExporter.class.php(324): wcf\system\importer\UserImporter->import(1, Array, Array)
#3 [internal function]: wcf\system\exporter\XF12xExporter->exportUsers(0, 200)
#4 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/exporter/AbstractExporter.class.php(154): call_user_func(Array, 0, 200)
#5 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/worker/ImportWorker.class.php(97): wcf\system\exporter\AbstractExporter->exportData('com.woltlab.wcf...', 0)
#6 /home/nginx/domains/servinglinux.com/public/wcf/lib/acp/action/WorkerProxyAction.class.php(93): wcf\system\worker\ImportWorker->execute()
#7 /home/nginx/domains/servinglinux.com/public/wcf/lib/action/AbstractAction.class.php(49): wcf\acp\action\WorkerProxyAction->execute()
#8 /home/nginx/domains/servinglinux.com/public/wcf/lib/action/AJAXInvokeAction.class.php(63): wcf\action\AbstractAction->__run()
#9 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/request/Request.class.php(58): wcf\action\AJAXInvokeAction->__run()
#10 /home/nginx/domains/servinglinux.com/public/wcf/lib/system/request/RequestHandler.class.php(139): wcf\system\request\Request->execute()
#11 /home/nginx/domains/servinglinux.com/public/acp/index.php(10): wcf\system\request\RequestHandler->handle('wbb', true)
#12 {main}