The official Ethereum Wallet (and Mist) have been deprecated for a while, and it's not recommended to use them anymore. You can find some alternative options on the Ethereum website here. If you're looking for a desktop wallet, I recommend MyCrypto's desktop application. It's fully open-source (see GitHub), and you can download it from https://download.mycrypto.com. It works on Windows, as well as macOS and Linux-based systems.