Tested under Microsoft Windows Server 2012 R2 Foundation.

ddclient, a dynamic DNS client for Windows.

Create a SPDNS account first! You need the account information during the setup procedure of ddclient. Register a SPDNS account

Login into your SPDNS account and setup a Host (5 are free).

You can choose your subdomain name (red box), a DNS Name of choice (green box), host type (IPv4 or IPv6) and set the IP to a initial value (default is the public IP of the machine you are using). This IP will be updateb by the ddclient updater later.

Install ddclient for Windows. You can enter the configuration details during the installation or later by editing the config file in a text editor.

Here is the config file. You have to replace all <SOMETHING> fields with your SPDNS account information.

# ddclient.conf
#
daemon=5m
use=web
web=checkip.spdns.de
server=update.spdns.de
protocol=dyndns2  login=<YOUR-LOGINNAME-HERE>, password=<YOUR-PASSWORD-HERE> <YOUR-DNS-NAME-HERE>.spdns.de
ssl=no