What is your email client?

To be able to diagnose the problem, I would need to know your email client ie: Outlook, Outlook.com Your ISP's email client, or address, Thunderbird, or one of the others. If it were just you, I could make an educated guess, but you say others in your immediate circle have the problem too. I would guess it's your copy of Windows that's bad, and that you used that same copy to install in your friends, and relatives computers that is causing the problems. When you find out what is causing your problems, you should share that with your friends, and family, to fix there problems.
As for what is causing your problem, I would contact your ISP. In many cases they can take control of your computer, and diagnose the problem there. If the problem is indeed with your computer, and not with the email client you use. In any case, it will allow another set of eyes to look over your problem, and maybe fix it.
Good luck, I hope your able to fix your problem.
The Masked Villian