Discuss this help topic in SecureBlackbox Forum
Authenticate with a key in PuTTY Key Agent
SSH-based client classes (TElSimpleSSHClient, TElSimpleSFTPClient) allow to authenticate using an SSH key store in Putty KeyAgent on Windows and OpenSSH Auth agent on non-Windows systems.
To use this authentication mechanism you should add SSH_AUTH_TYPE_PUBLICKEYAGENT option to AuthenticationTypes property of the corresponding class. Pageant or OpenSSH agent should be running in background for this mechanism to work.