The update KB5020387 bumps the version number to build 22000.1100 for Windows 11, and the update KB5020435 bumps the version number to 19042.2132 (20H2), 19043.2132 (21H1), and 19044.2132 (21H2) for Windows 10. According to the announcement (link 2), it only addresses an issue that affects some types of Secure Sockets Layer (SSL) and Transport Layer Security (TLS) connections that might have handshake failures. For developers, the affected connections will likely receive one or more records followed by a partial record with a size of fewer than five bytes within a single input buffer. If the connection fails, the app will receive the error “SEC_E_ILLEGAL_MESSAGE.” This problem only affects the original version of Windows 11 (version 21H2), not version 22H2, and the three most releases of Windows 10.

Download update KB5020387 for Windows 11

The update is available immediately and will download and install automatically. However, you can always force the update from Settings > Windows Update, click the Check for updates button, and use the option to install the update. On Windows 10, the option to update is on Settings > Update & Security > Windows Update. All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.