I can't bring up or send e-mails, also cannot take any downloads.
Issues with up and downloading data
There are a lot of potential explanations for your problems with emails and downloads. I think that is is probably best to tackle the issue on two fronts; first, the email client, and, second, your Internet connection generally.
Update your software
Without knowing more about the email provider and operating system you are using, we can start by making sure that all your programs are up to date with the latest software releases and patches. You should perform a manual Windows Update check for new Microsoft software. You should also make sure to update any non-Microsoft software you are using, like Internet browsers, email programs and security software.
Run security software and check internal connection diagnoses
Not being able to read and send email or download suggests that you might not be connecting to the Internet properly. I think there are two possibilities here as well; first, you might have acquired a virus or other malware program that is interfering with your connection and data transfers. You might want to consider downloading and running a program like Malwarebytes, which will scan your system for issues and attempt to repair any problems. There are also built in tools like scannow that you can run from within your Windows operating system. Once you are sure that your computer is clear, you can move on to troubleshooting your connection.
Check your Internet connection
In Windows, open the notification area, right click the network icon and then click to select Diagnose and repair. Follow the prompts to troubleshoot connection issues. You should also double check all cables and connections. Once done, reset your modem and router to make sure these connections are good. If you are unable to solve the problem this way, you might consider contacting your Internet service provider for help, or write again and offer more information about your operating system, email client and system. Good luck!