Why is my high speed connection slower with Web Shield on?

High speed connections greater than 20Mbits/s may see noticeable delays under certain conditions while Web Shield is enabled. For example, if a hard drive has an I/O speed of 30Mbits/s, the Web Shield can decrease the loading speed of a webpage because the hard drive I/O operations are doubled during active scans. In this case, the internet input of 20Mbits/s combined with 20Mbits/s of Web scanner data output then exceeds the maximum hard drive ability and can lead to noticeable delays.

Are there specific devices that have compatibility issues with Web Shield?

Some network components or connection types may be incompatible with a parts of Avast Antivirus or Web Shield in particular, as the default setting for some routers and ADSL modems may expect a different connection or packet type. This mismatch can cause connection resets and timeouts. Web Shield scans may also cause a device to time out if the device has a short timeout setting.

Avast monitors reports regarding specific devices and contacts device vendors about frequent issues with proposed coding solutions or workarounds. However, many issues are related to specific settings within Web Shield and can be disabled without eliminating your protection.

Are there any workarounds to improve web performance when using Web Shield?

You can customize your Web Shield configuration to improve web speed. This will have minor impacts on your security.

To adjust Web Shield settings:

1. Open the Avast Antivirus user interface and go to ☰ Menu ▸ Settings ▸ Protection ▸ Core Shields.
2. Scroll down to Configure shield settings and select the Web Shield tab.
3. Untick the box next to Enable HTTPS scanning to disable the setting. When enabled, the HTTPS scan protects your system against the malware delivered over HTTPS connections. When disabled, File Shield still scans all downloaded content before running any files.