Note: This thread so far is largely pointless, since without feedback from questioners, there is of course no way of knowing whether the many suggestions have:
A) Worked, or
B) Not worked.
The spirit of a forum is that we try to help one another by providing at least a minimal response to those trying to help. As things are, with no feedback - none at all - we still don’t know the cause of the problem, ten years after the original question was asked here.