After installing Avast Antivirus some 3rd party email clients, such as Mozilla Thunderbird, SeaMonkey, or The Bat!, may show that the mail server certificate is invalid when you send and receive emails.
The Mail Shield in Avast Antivirus uses an advanced scanning method for incoming and outgoing emails over SSL/TLS secured connections. Mozilla Thunderbird, Sea Monkey, and the Bat! have their own certificate stores and may require extra configuration to avoid warnings about invalid mail server certificates.
Refer to the sections in this article for instructions on how to stop warnings about invalid mail server certificates, export the Mail Shield certificate and import it into your email client's certificate store.
Export the Mail Shield certificate from Avast Antivirus
- Open the Avast user interface and select
☰Menu ▸ Settings.
- Select Components from the left panel, then click Customize next to Mail Shield.
- Select SSL scanning from the left panel and ensure the box next to Scan SSL connections is ticked, then click Export certificate.
- Select a location to save the exported Mail Shield certificate (for example, your Windows Desktop) and click Save.
- Click OK in the Avast Information dialog.
- Import the Mail Shield certificate into your mail client.
Import the Mail Shield certificate into your mail client
- Avast Ultimate 18.x
- Avast Premier 18.x
- Avast Internet Security 18.x
- Avast Pro Antivirus 18.x
- Avast Free Antivirus 18.x
- Microsoft Windows 10 Home / Pro / Enterprise / Education - 32 / 64-bit
- Microsoft Windows 8.1 / Pro / Enterprise - 32 / 64-bit
- Microsoft Windows 8 / Pro / Enterprise - 32 / 64-bit
- 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