Fix: Avast Not Updating Virus Definitions

Is Avast not updating virus definitions for some reason? You're not the only one with this problem so we created this nifty guide to help you fix this.

Avast is one of the world’s most prevalent antivirus software solutions. It is utilized by millions of people around the globe.

One of the main features of leading products such as Avast is auto-update, crucial for maintaining security in an ever-changing digital world.

However, Avast users sometimes encounter a problem where the software doesn’t update its virus definitions, leaving their system unprotected against new threats.

Using your PC while it’s unprotected can leave you very vulnerable on the internet, which is why we will be solving the problem in this guide.

Table of ContentsShow

The Problem Explained

Understanding why this problem occurs is important if you want to prevent it from happening in the future. If you aren’t interested in the causes and just want a solution, feel free to skip to the sections below.

Each antivirus program uses a virus database to help it identify threats, which is regularly updated as its developers become aware of new viruses.

When a novel virus is added to the database, the antivirus software can begin detecting it as something detrimental on your device and eliminates or quarantines it to safeguard you.

Avast is no different. It uses a database of known Virus Definitions to keep your computer protected. However, this only works if you grant the software permission to automatically update itself, sometimes even multiple times per day.

This setting is on by default, but there are sometimes compatibility problems, and the software can’t update. Fortunately, the solutions are simple and won’t require much of your time. Let’s take a look.

Fix 1: Enable Streaming Updates

According to an Avast representative in this Reddit thread, if you enable streaming updates in the settings menu, you will receive them more often.

We recommend doing this even if you are already regularly receiving updates.

Avast virus definitions not updating

Streaming updates are mini-updates that are usually just a few kilobytes large and are sent to your computer every few minutes. Frequently receiving these minor updates ensures you stay protected at all times.

Fix 2: Repair Your Software

Repairing your software can fix this problem, along with other known bugs. To do this, follow the step-by-step instructions below.

  1. Open Avast on your PC.
  2. Click Menu, then Settings. From here, open the Settings tab and then click General.
  3. To initiate the app-repair process, click on Troubleshooting and then Repair App.

Once the process is complete, reboot your PC and start Avast again. You should now receive updates regularly.

Fix 3: Uninstall Avast And Download The Latest Version

If you encountered issues while installing or updating Windows or Avast, it’s possible that you are using software that isn’t fully compatible with your current operating system.

This isn’t a typical scenario, but it can happen. This is why it is best to completely uninstall Avast, update your Windows, then download the latest version of Avast directly from their official website.


Now you know how to deal with the Avast not updating virus definitions problem on Windows. If none of the above fixes help, you should consider contacting Avast’s customer support team.

If they did resolve your issue, be sure to continue regularly updating your software to keep up with the latest database changes.

Related Reads

Twitch Error 403 – You May Not Change Your Display Name
Fix: Twitch Error 403 – You May Not Change Your Display Name
Bojan Veselinovikj

Bojan is a video-game developer and a tech enthusiast. Combining these two passions allow him to keep you informed on everything that's new in this fast-paced digital world.