Thanks that worked. Also, because I'm pigheaded I persisted in doing
it my way anyhow. I noticed the call was failing only on the first try.
On second and all subsequent tries it worked. The problem turned out to
be in sending the value of VolumeNameSize and FileSysNameSize. On the
first pass the values being sent were - 0. Code after the call would
properly set their values to 129, so on all subsequent calls the
parameters were passed properly. Answer - Spelling Error in setting
these two values to (misspelled) properties of my object.