Avast Antivirus: FAQs

Frequently Asked Questions

System Requirements

Download, Installation, and Upgrade

License and Registration

Features and Settings


What are the system requirements for Avast Antivirus?

For Avast Premier, Avast Internet Security, Avast Pro Antivirus and Avast Free Antivirus:

  • Windows 10 except Mobile and IoT Core Edition (32 or 64-bit); Windows 8.1 except RT and Starter Edition (32 or 64-bit); Windows 8 except RT and Starter Edition (32 or 64-bit); Windows 7 SP1 or higher, any Edition (32 or 64-bit); Windows Vista SP2 or higher, except Starter Edition (32 or 64-bit); Windows XP SP3, any Edition
  • Windows fully compatible PC with Intel Pentium 4 / AMD Athlon 64 processor or above (must support SSE2 instructions)
  • 256 MB RAM or above
  • 2 GB free space on the hard disk
  • Internet connection (to download, activate, and maintain updates of the program and antivirus database)
  • Screen resolution of at least 800 x 600 pixels
Avast Antivirus is not supported (is not compatible, cannot be installed, and will not run) on DOS, Microsoft Windows editions earlier than XP, Microsoft Windows Server operating systems, or any others not specified as supported.

Using Microsoft Windows operating systems without the latest Service Pack may not be supported. For details, refer to the documentation on Microsoft's website:

How do I download Avast Antivirus?

Download your preferred Avast Antivirus product using the direct links below:

How do I install Avast Antivirus?

For instructions to download and install your Avast Antivirus product, refer to the following articles:

How do I upgrade my current Avast Antivirus program version to the latest version?

If you have a valid license for an older version of Avast Antivirus, you can upgrade to the latest program version for free. For detailed upgrade instructions, refer to the following articles:

Is it necessary to uninstall a previous version of Avast Antivirus before installing a new version?

If you have Avast 7.x or later, you do not need to uninstall your previous version because Avast Antivirus setup automatically detects and upgrades the existing installation.

If you have Avast 6.x or older, you need to uninstall your version of Avast using the Avast Uninstall Utility, then install Avast Antivirus by following the instructions in the relevant article below:

How do I activate my subscription for Avast Premier, Avast Internet Security, or Avast Pro Antivirus?

You can purchase a license for Avast Premier, Avast Internet Security, and Avast Pro Antivirus via the Avast Store. To activate your product, follow these instructions:

  1. Open your Avast order confirmation email and copy the activation code.
  2. Right-click the Avast icon in the system tray and select Subscription information from the context menu.
  3. On the Your Subscription screen, click Insert activation code.
  4. Enter your activation code and click Next.
  5. Click OK.

For detailed instructions, refer to the following articles:

  1. Open your Avast order confirmation email and open the attached file (License.avastlic).
  2. Click Yes to insert the license file.
  3. Click OK in the confirmation dialog that appears.

For detailed instructions, refer to the following articles:

How do I register Avast Free Antivirus?

To register your Avast Free Antivirus, follow these steps:

  1. Right-click the Avast icon in the system tray and select Registration information from the context menu.
  2. On the Your Subscription screen, click Register now.
  3. Click Select in the Avast Free Antivirus column to continue registering Avast Free Antivirus.

For details, read the following article:

What should I do if Avast Antivirus does not accept my purchased license?

If you face issues activating Avast Antivirus, use the Avast webform to resend your license to the email address used for your purchase, then try to insert the license into the program again. If the activation code or license does not work, follow these troubleshooting steps:

  1. Uninstall Avast Antivirus using the Avast Uninstall Utility and restart your computer.
  2. Download and install the product version of Avast Antivirus connected to the purchased license.
  3. Insert the license into Avast Antivirus.

Can I get a copy of my purchased license?

If you did not receive your purchased license, you can request it via our webform using the email address provided for your purchase.

You can also download your license from your Avast Account. For more information, read the following article:

Can I transfer a license to another computer?

Yes. If you are no longer using your Avast license on one PC, you can activate the license on another PC and use your Avast product for the remainder of the subscription period. However, you cannot use a single license simultaneously on more than one PC. For more information, read the following article:

Can I use my license for Avast Antivirus to activate SecureLine VPN and Cleanup?

SecureLine VPN and Cleanup are integrated into the Avast Antivirus user interface, but require separate, paid licenses to use. You can purchase a license for either product from the Avast Store.

What is Software Updater?

Software Updater is a feature in Avast Antivirus that keeps commonly used third party software up to date to eliminate potential security risks. Malicious threats or attackers often use leaks in outdated software to access your PC. Software Updater displays the most popular programs installed on your PC and allows you to easily update them.

In Avast Premier, you can configure Software Updater to perform updates automatically. In Avast Internet Security, Avast Pro Antivirus, and Avast Free Antivirus, you can maintain updates manually by clicking the Update button next to each application.

What is Browser Cleanup?

Browser Cleanup is a feature now integrated into Smart Scan and Cleanup Premium.

When you run Smart Scan, your PC is scanned for various elements, including poorly rated browser add-ons. If such add-ons are detected, you can click Resolve All to remove them.

If you use Cleanup Premium, the Clean option scans for and identifies poorly rated browser add-ons. You can select which add-ons to remove, as well as view reputable add-ons.

What is Data Shredder?

Data Shredder is a feature in Avast Premier which allows you to irreversibly erase your files or whole drives, so that there is no way for anyone to restore and misuse your data.

When you erase a hard drive, or delete a file using standard tools, only a reference to its data is removed from the file system. Simply deleting sensitive files, such as user data or licensed software, may not be safe as there are tools capable of restoring deleted files. Data Shredder overwrites files with meaningless data multiple times before deleting them which prevents data from being recovered. Data Shredder is especially useful when selling/donating your computers or hard drives.

What is SecureLine VPN?

SecureLine VPN is a Virtual Private Network (VPN). A VPN functions as a private tunnel through the internet which encrypts your data and secures your connection when using public Wi-Fi connections such as those in cafes or airports. SecureLine VPN has servers in several locations which means you can bypass geolocation restrictions as well as access your favorite content while traveling.

SecureLine VPN is integrated into the Avast user interface, but requires a separate, paid license to use. For more information about SecureLine VPN, read the following article:

What is SafeZone Browser?

SafeZone Browser is a web browser with built-in privacy features from Avast. SafeZone Browser includes Bank Mode, formerly known as Pay Mode. Bank Mode creates a virtual desktop which acts as a clean and safe PC within your real PC. This virtual desktop isolates your activity from possible key loggers and allows you to perform financial transactions without fear of your personal data being stolen.

SafeZone Browser also includes several useful extensions: Ad Blocker, Passwords, Video-Downloader, and Safe-Price. For more details, read the following article:

What is Sandbox?

Sandbox is a virtualization tool in Avast Premier, Avast Internet Security and Avast Pro Antivirus which allows you to browse the web or run an application in a completely isolated, safe environment. When you run an application in Sandbox, your activity and web content is contained, which prevents damage to your PC. This is useful when you want to run suspicious or untrusted applications without risk.

What is Firewall?

Firewall is a feature available in Avast Premier and Avast Internet Security. Firewall monitors all network traffic between your PC and the outside world to protect you from unauthorized communication and intrusions. Firewall can prevent sensitive data from leaving your PC and can block attempted intrusions by hackers.

You can also set the application rules to control network and internet communication for specific software applications. Firewall applies these rules whenever a particular application tries to establish a connection to the internet or with another network.

What is Anti-spam?

Anti-spam is an additional installable component available in Avast Premier and Avast Internet Security. Anti-spam ensures that the inbox in your mail management software is free from unwanted spam and junk emails. This feature applies to mail clients installed on your PC, such as Microsoft Outlook or Mozilla Thunderbird.

Anti-spam is no longer installed by default. To install Anti-spam manually via the control panel, read the following article:

What is Game Mode?

Game Mode is a new feature in Avast Antivirus that improves the performance of your PC while you game by adjusting system settings and disabling unnecessary apps from running in the background. Each time you run a game, Game Mode automatically detects it and adds it to a list of game entries. When you run games from this list of entries, Game Mode automatically launches.

What is Real Site?

Real Site, formerly known as Secure DNS, is a feature in Avast Premier, Avast Internet Security and Avast Pro Antivirus which secures you against DNS (Domain Name System) hijacking. Some malicious programs can stealthily redirect you from an authentic URL to an inauthentic website to acquire sensitive information such as usernames, passwords, and credit card details.

Every time you enter the URL (address) of a website, such as www.example.com, into the address bar of your browser, the URL is translated to the IP address (Internet Protocol address) of the web server where the web page that you want to access is stored. Real Site provides an encrypted connection between your web browser and Avast's own DNS server to ensure that the displayed website is the authentic one.

What is Smart Scan?

Smart Scan is a comprehensive scan that detects the following:

  • Viruses: files containing malicious code which may impact the security and performance of your PC.
  • Vulnerable software: out-of-date software which hackers can use to access your system.
  • Bad browser add-ons: browser extensions that are usually installed without your knowledge and affect the performance of your system.
  • Weak passwords: passwords that are easy to decipher, used to access more than one of your online accounts, or compromised.
  • Network threats: vulnerabilities in your network that may lead to attacks on your router and network devices.
  • Performance issues: items such as junk files and unnecessary apps, or settings issues that may interfere with the operation of your PC.
  • Colliding antiviruses: antivirus programs that are installed on your PC in addition to Avast. Multiple antivirus programs slow down your PC and result in ineffective antivirus protection.

To run a Smart Scan, open the Avast user interface and go to ProtectionAntivirus, then click Run Smart Scan.

What is Wi-Fi Inspector?

Wi-Fi Inspector, formerly known as Home Network Security, scans your network for vulnerabilities and identifies potential security issues that open the door to threats. This feature checks the status of your network, devices connected to the network, and router settings. Wi-Fi Inspector helps you secure your network to prevent attackers from accessing it and misusing your personal data.

What is Cleanup?

Cleanup scans for unnecessary items and performance issues to create space on your PC and improve the speed of your system. After a scan, Cleanup offers to remove or resolve any found issues.

Cleanup is a paid feature which is not covered by an Avast Antivirus license. This feature requires a separate, paid license to use. Before purchasing Cleanup, you can click Check my PC to run an initial scan of your system and review any issues.

For details, read the following article:

What is Passwords?

Passwords is a password manager that allows you to use one Master Password to quickly and safely log into your online accounts and complete web forms. Passwords encrypts and securely stores your sensitive information, and enables you to synchronize your data across all your devices.

For details, read the following article:

What is Passive Mode?

Passive Mode disables all active protection, such as Shields and Firewall, so that you can use more than one antivirus program at a time without interfering with the performance of your PC or the reliability of antivirus detections. In Passive Mode, Avast Antivirus receives all virus definition and program updates which allows you to manually run scans to check for issues on your PC, however, Avast does not actively protect you.

If you want Avast to actively protect you from malware and other security threats, ensure that Passive Mode is not turned on and the following conditions are met:

For more information, read the following article:

What is Ransomware Shield?

Ransomware Shield, available in the latest versions of Avast Premier and Avast Internet Security, secures your personal photos, documents, and files from being modified, deleted, or encrypted by ransomware attacks. This feature scans for and automatically secures folders which may contain personal data and allows you to specify which other folders you want to protect from untrusted applications. Additionally, you can specify which applications are allowed to modify the files in your folders and which applications are always blocked.

Can I set Software Updater to automatically update my applications?

Avast Antivirus informs you when Software Updater detects updates for third-party applications. In Avast Premier, you can configure Software Updater to perform updates automatically.

In Avast Internet Security, Avast Pro Antivirus, and Avast Free Antivirus, you can maintain updates manually by clicking the Update button next to each application.

Avast aims to cover third-party products whose updates are essential for PC security. The products included may change over time.

Does my PC's performance slow down during an Avast scan?

Avast Antivirus comes with several pre-defined scans as well as the option to create your own custom scans and you can also create your own custom scans. Generally, running a scan does not noticeably affect system performance. However, performance may be affected somewhat depending on your system configurations, especially if you execute multiple scans simultaneously.

Does Avast Antivirus scan webmail accounts?

If you use a web based email account, such as Yahoo or Gmail, Avast does not directly scan your emails. However, Web Shield and File System Shield actively protect your PC from malware which could be contained in your email messages.

If you use a mail management software, such as MS Outlook or Mozilla Thunderbird, Mail Shield scans for threats in your incoming and outgoing email messages.

Can I adjust the sensitivity of Anti-spam?

Yes. If you want to adjust the sensitivity of the Anti-spam filter, open the Avast user interface and go to ProtectionAnti-spam. Select one of the following settings:

  • Relaxed: use this setting if too many legitimate emails are being marked as spam.
  • Strict (default and recommended setting): keep this setting enabled to maintain optimal spam filtering.
  • No mercy: use this setting if too many spam emails are getting into your inbox.
The higher the sensitivity, the higher the potential for false positive spam detections. Reducing the sensitivity reduces the chance of false positive detections, but may also reduce the effectiveness of the Anti-spam filter.

You can also adjust the sensitivity of Anti-spam from SettingsComponentsAntispamCustomize.

Can I turn off the Microsoft Windows Firewall when using the Firewall in Avast Premier or Avast Internet Security?

Yes. Avast Premier and Avast Internet Security include a built-in firewall. The Avast Firewall monitors all communication between your PC and outside networks and blocks unauthorized communication. It is highly recommended to keep all Avast protection components enabled at all times for reliable PC protection.

  • Avast Premier 17.x
  • Avast Internet Security 17.x
  • Avast Pro Antivirus 17.x
  • Avast Free Antivirus 17.x
  • Microsoft Windows 10 Home / Pro / Enterprise / Education
  • Microsoft Windows 8.1 / Pro / Enterprise
  • Microsoft Windows 8 / Pro / Enterprise
  • Microsoft Windows 7 Home Basic / Home Premium / Professional / Enterprise / Ultimate - Service Pack 1, 32 / 64-bit
  • Microsoft Windows Vista Home Basic / Home Premium / Business / Enterprise / Ultimate - Service Pack 2, 32 / 64-bit
  • Microsoft Windows XP Home / Professional / Media Center Edition - Service Pack 3, 32-bit

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