Hi Tatsuro, I guess it finally worked, although the bin directory should come first as read in the code of the batch file:
#***********************************************Rem Set up PATH. Make sure the octave bin dir
Rem comes first.
set PATH=C:\octave\Octave-4.0.0\bin;C:\octave\Octave-4.0.0
#***********************************************
Apparently I was able to install the 'struct' and 'optim' packages, since a star(*) symbol appears next to 'optim' and 'struct' when I call the package list as below
#
>> pkg list
optim *| 1.4.1 | C:\octave\Octave-4.0.0\share\octave\packages\optim-1.4.1
struct *| 1.0.11 | ...\Octave-4.0.0\share\octave\packages\struct-1.0.11
#
Once again, thanks for your patience and valuable help Tatsuro,
Sincerely,
Vinicio