Undefined variable: step

Fatal error: PHP notice in file /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/package/PackageInstallationDispatcher.class.php (163): Undefined variable: step
Information:


id: ecd6b4c1733f240836f5e45f0e30e1695c9344ca
error message: PHP notice in file /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/package/PackageInstallationDispatcher.class.php (163): Undefined variable: step
error code: 0
file: /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/WCF.class.php (309)
php version: 5.6.30-0+deb8u1
wcf version: 2.1.14 (Typhoon)
date: Fri, 14 Apr 2017 14:58:02 +0000
request: /acp/index.php?install-package/&&
referer: https://computer-fun-forum.eu/acp/index.php?package-installation-confirm/&queueID=1766&
Stacktrace:


#0 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/package/PackageInstallationDispatcher.class.php(163): wcf\system\WCF::handleError(8, 'Undefined varia...', '/var/www/vhosts...', 163, Array)
#1 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/acp/action/InstallPackageAction.class.php(73): wcf\system\package\PackageInstallationDispatcher->install('29cd4eb7')
#2 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/action/AbstractDialogAction.class.php(70): wcf\acp\action\InstallPackageAction->stepInstall()
#3 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/action/AbstractAction.class.php(49): wcf\action\AbstractDialogAction->execute()
#4 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/request/Request.class.php(58): wcf\action\AbstractAction->__run()
#5 /var/www/vhosts/computer-fun-forum.eu/httpdocs/wcf/lib/system/request/RequestHandler.class.php(139): wcf\system\request\Request->execute()
#6 /var/www/vhosts/computer-fun-forum.eu/httpdocs/acp/index.php(10): wcf\system\request\RequestHandler->handle('wbb', true)
#7 {main}