Go to NextUp.com and download the latest version (TextAloud 4 as of this writing). Install it. The trial runs for 21 days with full features. Use it to ensure your computer and the voices work for your needs.
When searching for a "TextAloud activation code," you will encounter two very different realities online. textaloud activation code
A: If you purchased TextAloud 3, you have two options. You can keep using TextAloud 3 with your old code forever. To upgrade to TextAloud 4, you will need to purchase an upgrade code (usually discounted to ~$20). A TextAloud 3 key will NOT activate TextAloud 4. Go to NextUp