UseTLS is a Published TIdUseTLS property that indicates the level of Transport Layer Security (TLS) required for control channel and data channel connections in the FTP client. 

Set UseTLS to one of the TIdUseTLS enumeration values to indicate the TLS security needed for the FTP client connections. 

The value in UseTLS is used in the Login method to determine if explicit TLS support is indicated for the control channel (ExplicitTLSVals) before performing the authentication indicated in the AUTHCmd property and establishing a connection using the optional values in ProxySettings. 

Changing the value in UseTLS may also alter other properties that depend on the TLS capacility. For instance, changing UseTLS to utNoTLSSupport forces the values in the following properties to be reset to their default values: 

Login 

ProxySettings 

DataPortProtection 

UseCCC 

AUTHCmd