All browsers to date still have a way to lockup on a screen like that. That's part of the scam to get the user to think it's infected.
This is called Rogue Security Software by Norton, Microsoft and others. While it's hard to infect a PC in this manner without some help from the user (you did the right move by ending the task) Grif has some tools to scan with.
I suggest WOT (Web Of Trust) to help avoid these sites in the future.
1. WOT for Chrome is at
https://chrome.google.com/webstore/detail/wot/bhmmomiinigofkjcapegjjndpbikblnp?hl=en
2. Grif has a set of scanning tools (all free, will remove what they find) at
http://forums.cnet.com/7726-6122_102-5509131.html?tag=posts;msg5509131
Bob
Hi - newbie here, so sorry if this has already been addressed. Searches of the phone number and "mycpuscanalerts" brought up nothing.
So... I was using Google Chrome this morning when another tab popped up on its own with this message (screen shot linked at https://www.dropbox.com/s/qni4pitoo7cni2z/Security%20alert%20snip%20from%20computer.JPG?dl=0).
Something like this happened once before and I remember being unable to cancel or get out of it without simply doing the end-task process and "ending" Google chrome. So that's what I did - control, alt, shift -- and ended Chrome. When I started it again -- no problem.
I searched the phone number and found a reference in an Apple forum. I'm pretty sure it's bogus, but what -- other than running a Kaspersky scan -- should I do? Has anyone on here had this experience?
Thanks.

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