There have been some reports about issues with the Updater not updating anymore. Please try the latest beta version and switch to another IP Check provider instead of the previous default dnsomatic.com. For some reason they are rate-limiting the number of requests to their service. The new IP Check provider selection allows you to choose another provider in such cases. You can test the functionality with the new "Test" panel.
Free dynamic DNS updater application for WindowsDownload Stable Release
Your router does not support the service providers DNS-O-Matic, DynDNS, No-IP, OpenDNS, selfhost.de, spDNS (medical-it-services.de) or STRATO by default, or is limited in the number of dynamic DNS providers?
You can use this simple client to send IP changes to your dynamic DNS account automatically.
Marcs Updater is built for Windows and runs under Windows XP SP3 or newer.