Mel

A correction:). Adding ppt.delete does not solve the problem of the activeX server running ahead on itself as I claimed in my last comment:).

There is though a simple solution which also makes export of many figures much faster. Just give an array of figure handles as an additional argument to the function and move the loop over the figures into the application. Something like

function savepptmany(filespec, figvec, titletext, prnopt)
[...]
% Start an ActiveX session with PowerPoint:
ppt = actxserver('PowerPoint.Application');

if ~exist(filespec,'file');
  % Create new presentation:
  op = invoke(ppt.Presentations,'Add');
else
  % Open existing presentation:
  op = invoke(ppt.Presentations,'Open',filespec,[],[],0);
end

% Loop over figures
for addfig = 1:length(figvec)
  figure(figvec(addfig));

  % Capture current figure/model into clipboard:
  if nargin<3
    print -dmeta
  else
    print('-dmeta',prnopt)
  end

 % Get current number of slides:
 slide_count = get(op.Slides,'Count');
  
 % Add a new slide (with title object):
  slide_count = int32(double(slide_count)+1);
  new_slide = invoke(op.Slides,'Add',slide_count,11);

  [...]
  % Center picture on page (below title area):
  set(pic1,'Left',single((double(slide_W) - double(pic_W))/2));
  set(pic1,'Top',single(double(slide_H) - double(pic_H)));
end

if ~exist(filespec,'file')
  % Save file as new:
  invoke(op,'SaveAs',filespec,1);
else
  % Save existing file:
  invoke(op,'Save');
end
  [...]
Note that titletxt has to be cell array of strings now.