Article ID: 127910, created on Dec 28, 2015, last review on Dec 28, 2015

  • Applies to:
  • Web Presence Builder 11.5
  • Plesk
  • Plesk Sitebuilder
  • Plesk Expand


If you use any of the following product versions:

  • Plesk for Linux 7.1-8.2.1
  • Sitebuiler for Linux 1.x-2.1.3
  • Virtuozzo containers for Linux 2.6.1, 3.0.0

and have issues with license update, refer to this article:

  • 126447 License fails to update or upgrade (legacy product versions)

For other products and versions, please see the resolution below.


The product license fails to update. The following errors may occur:

Licensing Server Unreachable: Unable to connect with licensing server.
Please make sure that your network allows communication to
For more details check system help pages.


Couldn't resolve host name


Can't connect to (Timeout)


The product tries to connect to the license server at port 5224 to update the license, but it cannot establish a connection.


On December 1, 2014, the IP address of the license server was changed to (IPv4) and 2001:67c:730::80 (IPv6). Make sure that the hostname resolves to the proper IP from your server:

# nslookup

If the license server does not resolve to the correct IP, check the /etc/hosts file.

If any of these servers are behind a firewall and old IP addresses of Key Administrator are listed in the firewall rules, please add new IP addresses of Key Administrator to the firewall rules to allow your servers to connect to This can be checked with these commands, depending on your OS:


# nmap -P0 -p5224
# telnet 5224
# traceroute


telnet 5224


Note: Telnet Client should be installed additionally for Windows -> how to install Telnet Client

If you are using the APF firewall, check /etc/apf/allow_hosts.rules for the mentioned IPs or the hostname

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