When you download software, your browser may only give you the option to save the install file or it may automatically save the file to a default location.
For many, that default location is C:\Users\[username]\Downloads. If you can't find the file there, open Windows Explorer (click the start button or use the keyboard shortcut Windows Logo + E) and type "ta19" in the search bar. Note: The filename ta19 indicates a 2019 TaxAct file. A filename of ta18 would indicate a 2018 TaxAct file.
If you can't find the file by searching your computer, try typing the keyboard shortcut Ctrl + J in Internet Explorer, Firefox or Chrome.
Once you find the downloaded file, double-click to install.