Hi, There is actually quite a complicated issue with the abort vi call through activex. It does work in many cases, but is failing when there are multiple references of a vi open at the same time. Abort VI does work via activex, just make sure you are closing un-needed references. Try making a very simple program in VB to do this, I have tried this in LV and can abort any VI thats running, my VB isnt up to much i'm afraid.
The fix for the bug is scheduled for the next version of labview. One work around that i came up with, is to make use of some of the activex calls you can make. If you have a stop control on the front panel in lv, set the tab order so that it is first in the list. Then in VB, get the property of panel, then of controls (which is an array of references of all controls & indicators), index the first element of that array, then you can change the value property of that reference. This programatically stops the program rather than aborting it, which is safer when doing any hardware I/O. Obviously the stop control in labview must be programmed to actually stop the VI. Dont forget to close each reference, that includes the array of control/indicator references. Hope that helps, even if the bug exists in the current version of LabVIEW. Anthony Sims Applications Engineer NI-UK