Cygcrypto11dll 2021 ((full)) -

If the error appears when launching a non-Cygwin app (e.g., a custom tool), that program was likely built with Cygwin dependencies. Reinstalling the app from its official source should restore the missing DLL.

The file is a critical security library used by the Cygwin environment to provide OpenSSL cryptographic functions to Linux-based applications running on Windows. Core Functionality cygcrypto11dll 2021