Strange popup window when Weather Watcher starts

Since changing file servers yesterday, Weather Watcher (all versions before 5.0.27) is looking in the wrong location to check for new updates. The popup looks like:

To fix the problem, simply download and install the latest update from the following URL:

Please note that the popup is not spyware, spam, etc., as some people thought. It includes a web site called…. which is one of my file mirrors.