Windows 7 is no longer being updated by Microsoft for newer security features, so you will not be able to connect to some servers.
The way to work around this is to download the resources on a different computer that has Paratext installed on it and then copy them to a USB drive that you can use to transfer the files to the Windows 7 computer.
Downloaded resources are in the C:\My Paratext 8 Projects_Resources or C:\My Paratext 9 Projects_Resources folders by default and have .p8z as the extension.