Schannel Error Codes for TLS and SSL Alerts
Schannel returns the following error messages when the corresponding alert is received from the Transport Layer Security (TLS) or Secure Sockets Layer (SSL) protocols. The error messages are defined in Winerror.h.
Article text from the Win32 documentation (opens in a new tab), by Microsoft, under the CC BY 4.0 (opens in a new tab) licence.