Indeed, the download is possible through the download page at Software Informer, but the website that provides the actual poker service is discontinued, meaning that it can't be reached. That's why you've received the connection error message.
Unfortunately, it's impossible to say when or how will it come back, which means that you have to use an alternative to play poker.
Luckily, there are plenty alternatives available. Follow this link to get see them: http://software.informer.com/search/online+poker