A password-encrypted key is generated from a user-supplied password or other identifying data and then used to encrypt the user’s password. The LWPCS defines joint and weld quality attributes as process control variables and integrates these weld quality variables, along with the more traditional process parameters such as laser power, wire feed, GMAW voltage and active seam tracking, into a closed-loop monitoring and control system. The interceptor selects information useful in determining the cause of a failed usage of the service residing in the client server from each intercepted invocation and response messages, writes the selected information to a data store residing in the client server and then re-invokes the intercepted invocation and response messages.