Welcome to Justanswer.com, my name is ***** ***** I will do my best to assist you.
What you have encountered is a very common phone scam.
The company who you called, was the same company who made the virus that told you to call them.
In fact this scam is so common that it works in your favor. Call your bank immediately, or your credit card. Let them know you fell victim to an online virus / scam. And challenge that charge. The bank will revers the charge. You will get your 400$ back.
And then its just a matter of making sure that the other company did not install any keyloggers. And also, that you did not give them any of your email or account passwords.
Youre best bet at this point is to do a reset on windows 8.. Wiping out everything. Heres an easy way to do that.
Once you have wiped everything out and reinstalled windows. ( remember, if you want to keep any pictures or files you have saved on the computer. Save them before you reset Windows 8 as described above !!)
As long as you didnt give them any passwords. After you call and dispute the charge, and then run the reset I mentioned.
You will have your money back and also, you will have a clean computer free of whatever programs they attempted to install.
If you have any further questions or concerns, let me know~ And also, should you encounter any strange programs or companies asking you for money, passwords or anything else. I invite you to contact us again, a low cost consultation can save a lot of time and heartache~ ( and $$ )
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Senior Technician and Network Switching Systems Operator / Maintainer.
Swipe in from the right edge of the screen, tap Settings, and then tap Change PC settings.
(If you're using a mouse, point to the upper-right corner of the screen, move the mouse pointer down, click Settings, and then click Change PC settings.)
Tap or click Update and recovery, and then tap or click Recovery.
Under Remove everything and reinstall Windows, tap or click Get started.
Follow the instructions on the screen.