Thank you for your reply CAB
I arrived at the same result that you, namely that the setxdata does not work, despite a safearray correct.
I asked to see if someone had not found a trick and circumvented the problem.
Apparently not
It is still surprising that we can add, but not delete.
The only method is dond use _.vplayer, but when the viewport is not active layout, I do not see how
@+