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SOS Informatique Computer repair in Lyon - Individuals and businesses

"Your PC is infected" : the fake security alert

If a page shows a phone number to call urgently, it is a scam. No software company works that way, ever.

It is the most reliable sign there is, and it settles the matter on its own. Microsoft, Apple, your antivirus : none of them will ever put a phone number in an alert. That mechanism exists only in the fake tech support scam.

What the trap looks like

You are browsing, sometimes on a perfectly honest site carrying a poisoned advert, and a page opens full screen. It copies the colours and the logo of Microsoft or of a well-known antivirus, lists made-up error numbers, claims your bank details are exposed and that your files are about to be deleted. Sometimes an alarm sounds, a synthetic voice speaks, and the page refuses to close.

All of that is just a web page. It has access to nothing on your machine, it has scanned nothing, and nothing is infected. Its only purpose is to get you to dial the number.

Closing the page

If the close button does not respond, the page is using full-screen mode or a loop of windows. Two ways out :

  1. Press the Esc key, held for a few seconds, to leave full screen, then close the tab.
  2. If that is not enough : Ctrl + Shift + Esc opens Task Manager. Select the browser and click End task.

When the browser starts again, refuse to restore the tabs: otherwise the page comes straight back. That is the classic mistake that makes people think the problem is still there.

If you called the number

Install nothing, give no code, hang up. If you have already allowed remote access, treat the machine as compromised : that person had access to your files and to whatever accounts were open. Switch the computer off, uninstall the remote access software from another device if you can, change your important passwords from another device, and keep an eye on your bank accounts. See after a fraudulent link.

And if you paid ?

Contact your bank immediately to try to stop or dispute the payment. Keep everything : the number you called, the amount, the name of the software installed, screenshots. A police report is possible and often asked for by the bank.

Be especially wary of what comes next : victims are frequently called back a few weeks later by a supposed service offering to "recover the funds", which is simply the second half of the same scam. Never engage with that kind of call.

Stopping it happening again

  • An ad blocker greatly reduces your exposure, since these pages usually arrive through advertising networks.
  • Always refuse the notifications offered by websites : they are used to display fake alerts even when the browser is closed.
  • If alerts appear outside the browser, then a program really is installed - see adverts that open by themselves.

Having the machine checked

After an episode like this, a check is reassuring and does not take long : an offline scan, a look at the installed programs, the browser extensions and any remote access software. It is easily done remotely. We describe the current variants on our scams page.

Frequently asked questions

Is my computer really infected when that page appears ?

No. It is an ordinary web page that has scanned nothing and has access to nothing. The message is entirely fabricated to provoke a phone call.

Can Microsoft call me about a problem on my computer ?

Never. Microsoft does not call private individuals and has no way of knowing that your machine has a problem. Any such call is a scam.

Does Windows need reinstalling after fraudulent remote access ?

It is the only real guarantee if the person had full access. A cleanup may be enough in mild cases, but examining the machine is what settles it.

Further reading

Would you rather we took care of it ? See our virus removal and cleanup service, in Lyon and across the Rhone.

Still uneasy after a suspicious alert ?

A full check of the machine, remotely or at your home.

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