My guess is that you're looking in the wrong context. If you scroll to the top of the heap list (the one you show in the image above), you'll see that they're broken up into contexts. In general, there are two contexts you will encounter: the Main Application Instance and Project contexts. The Main Application Instance contains VIs opened without a project. Project contexts have the VIs in a project that are on a specific device (i.e. My Computer or an RT Target). There are tons of other contexts that handle internal stuff, but your VI shouldn't be in those. Check all the contexts that sound relevant to your VI. If that doesn't work, I'll forward this to someone who knows better than I. I just use Heap Peak -- I've never seen how it works on the inside.