Occasional problems with special pasting in powerpoint

[CecileBF]

Hi,
I used the special pasting as Object Linking and Embedding (OLE) for integrating graphs in a powerpoint presentation which I and my colleagues update regularly.
It works quite well, however sometimes, especially as I am manipulating the original workfile, the graphs can disappear. It seems to be a bug, am I the only one experimenting it? As I don't really know the reason of these occasional disappearances, I try not to manipulate the workfiles containing the graphs/the programs creating them as the same time as the powerpoint file. But I don't know the exact reason behind this problem (the link of the disappeared graph is still listed in the window "Links" when I open it).

[EViews Gareth]

I've seen it happen a couple of times, but the bug appears to be within Powerpoint (I've had them disappear when linked to other applications too, not just EViews)

[CecileBF]

Thank you! So I guess since the cause remains unknown, there is no clue on ways to avoid them? Or are there ways to prevent them?
Or should I contact Microsoft directly?