The Avast Certificate Error is an annoying error that indicates that a site’s SSL certificate is invalid or expired. For the most part, this is not true and is just a misunderstanding from the antivirus’s point of view. 

Usually, Avast antivirus software comes with an in-built SSL scanning feature to scan incoming and outgoing internet traffic. In addition, they install an invisible SSL Certificate Authority in web browsers or embed it in the internet settings. 

This SSL scanning feature is available in Avast Web Shield and Avast Mail Shield. Therefore, Avast Web Shield scans SSL certificates for websites while Avast Mail Shield scans email servers like Gmail and Outlook. 

As a result, users can face Avast Certificate Error when they’re trying to access their emails or a website. 

What are the Causes of Avast Certificate Error 

Usually, there are no particular reasons for Avast Certificate Error. However, the SSL certificate could be indeed expired or invalid. Therefore, you should check the website’s certificate and continue only if you trust that site. 

In addition, these errors are mostly faced when users are using third-party email clients in their browsers. 

How to Fix Avast SSL Certificate Error

The Avast Certificate Error can usually be resolved by simply disabling the SSL Scanning feature. Generally, this is not recommended as they can provide less security. However, you can easily turn the feature on or off depending on your needs. 

To begin with, you can try these quick fixes before you head over to the specific solutions. 

  • Check your computer system’s date and time 
  • Update Avast Antivirus to the latest version
  • Delete your browser’s site data, cookies, and cache  
  • Reset your browser settings 

Solution 1  – Disable HTTPS Scanning Feature 

The HTTPS scanning feature is present within the Avast Web Shield of Avast Antivirus Software. Hence, this can cause Avast Certificate Error when you’re trying to visit certain websites. 

However, you should check the actual certificate of that website before you disable the HTTPS scanning feature. Follow these steps to disable the feature from your antivirus software. 

  1. Firstly, open the Avast antivirus software. Next, head over to Settings and go to Active Protection.
  2. Here, you need to find ‘Web Shield’ and then click on the Customize option. 
  3. Go to the Main Settings section.  
  4. Finally, make sure that Enable HTTPS scanning is unchecked.
  5. Save your settings and close the program. 

Solution 2 – Disable SSL Scanning Feature 

In addition to the HTTPS scanning feature, there is another SSL scanning feature for IMAP servers. These IMAP servers are mail servers that is used by email accounts. 

This is different than HTTPS scanning feature and needs to be disabled in another way. You can disable the SSL Scanning feature by following the steps given below. 

  1. Launch the Avast Antivirus program and then go to Settings.
  2. Next, go to the Active Protection Lab. Here, you have to click on the Customization button next to ‘Avast Mail Shield’. 
  3. You will see an SSL Scanning Window. Here, you need to uncheck Scan SSL Connections. 
  4. Finally, close the program after following the above steps. 

Solution 3 – Export Avast Mail Shield Certificate 

Accordingly, there is another way to resolve the Avast Certificate Error in your system. You can do this by exporting the Avast Mail Shield certificate. Subsequently, you have to import the same in your email clients. 

First, you need to follow the steps mentioned below to export the certificate from Avast. 

  1. Go to the Settings menu from Avast’s main window. 
  2. Navigate to General from the left pane and then go to Troubleshooting. 
  3. Here, head over to Open Old Settings and then select Components. 
  4. Next, click on the Customize button next to the Mail Shield. Here, you have to go to the SSL  scanning window. 
  5. Finally, you will see an option to ‘Export Certificate’. Navigate to the folder of your choice and save it. 

Subsequently, you have to import the same into your mail clients. 

To summarize, the Avast Certificate Error should be resolved by following the fixes mentioned in this article. 

In addition, some users have said that you can deselect IMAP servers from not getting scanned. Hence, doing this might resolve the error as well.