If you have no antivirus programs installed or your current antivirus program has expired and asks money for updating, I recommend avast! Free Antivirus 8 (previously named avast! 4 Home Edition or avast! 5, 6 or 7 Free Antivirus), because it is free for home users and it provides good overall protection from viruses and malware by scanning also network and instant messenger traffic unlike many other free antivirus programs. Its only downside is that it requires re-registration once a year, but it is still free and not difficult.
avast! Free Antivirus works in Windows XP, Vista, 7 and 8.
If you have some other antivirus program installed, remove it first!
As more than one antivirus program makes your computer slow, it is very important to first uninstall the currently present one. Also, several well-known antivirus programs and tools by McAfee and Symantec/Norton do cause errors (for example, "Setup GUI was not initialized successfully") while installing avast! Free Antivirus. Please remove other virus protection programs completely, including scanning tools such as McAfee Security Scan. More troubleshooting options are described in the end of this article.
If you do not have an antivirus program installed, move down here.
If you have previous version of avast! Antivirus (such as version 5, 6 or 7) installed, don't worry - your program will be updated and your license will remain intact. Move to the upgrading part for quicker installation.
In Windows XP, click the Start button or press Windows Key on your keyboard and choose Control Panel. Windows Vista, 7 and 8 users, move down here.
Click here to show or hide instructions for Windows XPIn Windows Vista or 7, click Start button or press Windows Key on your keyboard to open Start menu. Then type "remove" into Start menu Search box and click Add or remove programs. If you have Windows XP installed, check instructions above.
In Windows 8, open Settings Search using keyboard shortcut Windows Key+Q, type "uninstall" into Search box and then click Uninstall a program. Alternatively, use keyboard shortcut Windows Key+X to open the list of system tools and click Programs and Features.
Downloading avast! Free Antivirus 8
In case you have an older version of avast! Free Antivirus installed already, use the simpler and faster upgrade process instead.
If not, go to avast! Free Antivirus download page and click Download button in the Free Antivirus column on the left.
In case avast! offers something to buy, click No thanks, I want free protection.
You will be taken to CNet's Download.com page. Click the green Download Now button.
Installing avast! Free Antivirus 8
After downloading, launch the setup program if it did not run automatically.
In the Choose your solution screen, click Install avast! Free Antivirus.
Now this is really important! In the Please configure your product screen, clear all available check boxes, such as Yes, install Google Chrome as my default browser or Yes, install Google Toolbar for Internet Explorer. Never-ever install additional programs with an downloaded package. Although neither of the offers is malicious or bad per se, you should not add programs or toolbars you do not really use or need.
Then leave Express Install selected and click Next.
Installation information screen opens, click Next again.
Then avast! Free Antivirus Setup reminds you that some personal information is gathered, but it will never be used to identify you, or shared with third parties. Click Next.
Installation starts with creating a System Restore point. This takes a minute or so. Just stand by - after this the program will be installed. A quick scan might also be performed.
After the installation is complete, it is time to enter a working e-mail address to register your free product. I wouldn't really recommend registering with Facebook, as the latter is known to leak information to third parties. If you still want to use Facebook, read this article on how to minimize data leakage possibilities on the most popular social networking site before clicking on the blue Register with Facebook button.
Those who do not prefer (or have) Facebook, type your e-mail address and click Register with email address. A confirmation message should arrive in the provided inbox shortly and you must click the included activation link to enjoy your free product. This will also create your avast! account at https://my.avast.com if you do not have one.
You might have to restart your computer before the avast! Notification Area (System Tray) icon appears.
After a restart, you might see an offer to install avast! EasyPass, but as this is a paid product, clear the check box and click Finish. I recommend using free Password Safe instead.
This completes the downloading and installing part. Read about configuring avast! Free Antivirus next.
About avast! Account
avast! Account is a free service that can be used to monitor the status of avast! Free Antivirus on Windows and Mac computers. Android devices can also be located, remotely locked and wiped.
To verify that your current computer is connected to your avast! account, click Settings on the top right of avast! user interface (main window). Open Account tab on the left and check if Current Status reads "Connected". Also, make sure the Report program status to the avast! account check box is ticked.
In case Current Status is "Disconnected", you can click the Connect now button.
The following process looks exactly like registering for a free license, but without ads for paid products.
In the Add this device to your avast! Account window, enter Your Email and click Sign in with email address. If you do not have an avast! account, you'll receive an e-mail with activation link shortly.
Again, using your Facebook account is not recommended, because the social networking giant likes to share your private information with third parties.
In case you already have avast! Account, type your password for it in the next window. Forgotten passwords can be reset using the Forget password link.
You can access your avast! Account any time by browsing to https://my.avast.com or by opening Account menu in avast! Free Antivirus 8 main window and then clicking on your e-mail address.
Open Devices tab to see a list of your connected computers (Windows or Mac) and Android devices. Security Status should read "Secured" for all devices. If it reads "Off" instead, there has been no communication between the device and your avast! Account for a longer time.
Clicking the View Details button gives an overview and latest logs for the device. Android devices can also be located, locked and wiped remotely.
Always click the Log Out link on top right after you've finished using your avast! Account.
Upgrading to avast! Free Antivirus 8 from an older version
In case you have an older version of avast! Free Antivirus installed already, open avast! Free Antivirus by clicking its orange ball-shaped icon in Taskbar Notification area (aka System Tray).
If a program update is available, you'll see the Program version line in red and an Update button is available. Also, a yellow ring with white exclamation mark is displayed. If the same yellow ring appears in the Virus definitions version line, you should update virus definitions as soon as possible (the Update link or button is available on the right).
Else, click Maintenace tab on the left and open Update. Then click Update Program.
Wait until avast! downloads and installs the updated files. This might take several minutes, but this will certainly be much quicker than downloading the whole setup package.
After the latest version has been installed, you will probably have to restart your computer. Click Yes in the dialog.
This is important! After a major upgrade, different offers to install Google Chrome and Google Toolbar for Internet Explorer might appear.
Please clear any check boxes before clicking Finish - remember not to install any browsers, toolbars or other software with a free or paid product!
In case you get errors during installing or upgrading, such as "Setup GUI was not initialized successfully" and "You are trying to use an old version of the avast setup", please verify that you do not have any other anti-virus programs or tools (especially those by McAfee and Symantec or Norton) installed. If you do, uninstall those and try again. Also, make sure you've downloaded the latest version from avast! Free Antivirus download page. The setup file does get updated from time to time.
If you have no other anti-virus programs running, download avast! Cleaner to your Desktop (or some other folder) and start Windows in Safe Mode. Run the downloaded program to clear all avast! files and settings that might cause conflicts and errors. Restart your computer, let Windows start normally and try running avast! Free Antivirus setup again.
Updating avast! Free Antivirus 8
Please do not confuse program updates with virus definition updates! Program updates mean minor program changes that improve performance, features or protection. For example, from version 8.0.1483 to 8.0.1489. Program updates normally require a restart.
In most cases, avast! updates itself automatically (if configured to do so), but you can always check if you have the latest version installed by opening avast! main user interface, opening Maintenace tab and clicking Update on the left.
If there is a line "A new version of the program is available! Latest program version: <some number>" visible, you can click the Update program button.
A promotional sales offer appears next, titled New avast! version 8: choose an update. Click the grey Update button on the left (Essential update column). Remember, we're talking about free version here! 

avast! then downloads all required update packages and applies them. This might take a while - sometimes even up to 20-30 minutes.
After the process is complete, a restart prompt appears. Click Yes to reboot your PC.
This is again important! After you log back in, you will see another promotional offer. Please clear all check boxes on the bottom left of the Complete your avast! software update window. There is absolutely no need to install additional web browsers and toolbars!
Then click Finish.
Those who already have Google Chrome installed, will see the Complete your update by adding the avast! Online Security plugin for Google Chrome offer instead. This is just a rebranded version of avast! WebRep/Antiphising/Sitecorrect extension, so you can safely close the window.
That's it!




