Over the years there have been many scams claiming to be corporations , some claiming your credit card needs updating asking for your information , others that email you looking just like your bank and those who claim you have errors on your system and they need to gain access of it to clean it.
If you have anyone asking for your credit card info hang up and call the company direct this will save you a lot of trouble trying to get your funds back.
Never click on a link in your email claiming to be your bank without contacting the establishment first.
If anyone calls you to tell you that there are errors on your computer the first question you should ask yourself is how would they know? Trust me such establishments like Microsoft or Apple will never contact you to make you aware of this , you are the only person who should know that you have errors on your system , and never never let any of those take remote access of your computer , it's very dangerous and sadly some of those that have fallen for it have lost thousands of dollars.