AuthProxyRetries is an Integer property that represents the number of retries attempted when performing proxy authentication for the TIdHTTP client connection. 

AuthProxyRetries is used when an HTTP protocol handler for the client connection attempts to process a protocol response code that indicates authentication or proxy authentication is required (401 or 407). 

AuthProxyRetries is compared to the current maximum number of authentication requests allowed in MaxAuthRetries to determine if additional proxy authentication requests are allowed. When permitted, the request is performed using the OnAuthorization event handler.

TIdCustomHTTP.AuthRetries 

TIdCustomHTTP.MaxAuthRetries 

TIdCustomHTTP.OnAuthorization 

TIdHTTPProtocol