Originally Posted by Ash

No problem, we're here to help. I hope you can help us by coming back often and posting, rather than never returning now that we've spent time helping you.

What security software is on the computer? I suggest that you use Comodo Personal Firewall along with Avast Antivirus Home Edition, with Windows Defender. Also install the Firefox web browser for your mum - you can get it from this link: http://www.compuforums.org/get-firefox.html
With this software installed, your mum won't need to worry about any security problems. All of these programs update themselves automatically and they are all free.