A TACACS+ user named "bluecoat" has touch account permission. This user enters the CLI command to change the touch password:
PacketShaper# setup password touch
Old touch password: Authentication failed.
This is expected behavior for PacketShaper S-Series. For security reasons, a TACACS+ user with 'Touch' permission cannot change PacketShaper S-Series's Local "Touch" Account's password.
sys event display command output also indicates error
926 [0427403.2480] I: command_execute: set password touch (NULL) (NULL)
927 [0427403.2480] A: accessChangePassword: Password change failed: touch authentication
To change local touch account password, log in to PacketShaper S-Series with the local touch permission account via serial console or SSH.