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How do you safely install virus protection - when you don't yet have virus protection? A firewall is very good security. That plus one other practice should keep you safe.

I recently did a clean install of my OS, but I did not backup my antivirus software and had no way of getting one, so I decided to download one from the internet with only the firewall running: Windows firewall and no security patches for Windows had been updated either. Was this a bad idea? And what were the chances of getting infected by doing something like this?

In this excerpt from Answercast #10, I talk about downloading anti-malware tools (from a trusted source) when starting up a machine from a clean install.

Downloading virus protection software

It was not a bad idea.

I typically do something like that myself when I start up a new machine and start fresh.

Will you get infected?

What are the chances? Pretty low.

Here are the ways you protected yourself:

  • One, Firewall is on

Make sure that the firewall is on as soon as possible. In fact, most current versions of Windows do that for you automatically. They start with the firewall turned on. That prevents malware out on the internet from accessing and infecting your machine.

  • Two, download security first

The next most common way that malware infects your machine is to be invited in. By that I mean, you click on a bad website; you download a file that's infected; you open an infected attachment in email.

As long as you avoid all of that, don't start surfing the web, don't start downloading other files, don't start opening attachments that are in your email, you should be fine. Focus first on downloading your anti-malware from a trusted source and then installing those.

'You done good!'

In my opinion, that is not just reasonable. That's a pretty safe way of bootstrapping the security of your system.

So offhand, I'd say the chances are pretty low to get an infection, and you done good!

Next - Can a virus be transferred into our system, or our router, from our granddaughter's smart phone?

Article C5225 - April 19, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Rosie Perera
April 19, 2012 12:02 PM

Only once, when I was setting up a new machine from scratch, did I get a virus as soon as I went online to download my anti-virus software. Some random IP address attacker must have gotten me. That's the only time I've *ever* gotten a computer virus in my life. But I didn't have the Windows firewall turned on. Big mistake! I always make sure I have the firewall enabled first thing now.

Alex Dow
April 20, 2012 8:53 AM

Additionally, why not simply copy over any A-V software available on your old PC, using say, an SD Card, before you even think about going on-line?

I usually save such software in a DOWLOADS Directory, with Sub-Directories (Folders) for different ones.

So even if slightly out-of-date, they are likely to provide more protection, than nothing.

Stanley Keil
April 20, 2012 12:02 PM

Have a copy of an anti-virus (Avira, Avast, AVG, etc) on a flash drive or CD/DVD. Download and install it on the 'new' machine before it's connected to the internet.

April 20, 2012 1:08 PM

I've re-installed my OS several time in the past few years and I always save my anti-malware apps on a flash drive along with any apps I think are necessary (for me).
That way I can have the good guys up and running before I get online and the first thing I do is update them.

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