Well, in regard to 2. - we also have it randomly.
Regarding 1. - do you mean you only have one exe, and it never calls another exe? Then the problem is worse than I thought, and I am very surprised that it does not affect everybody. I thought that the problem is limited to calling one exe from another, and that maybe very few apps do that.
In any case, I don't know if the cause of "Class Definition X is not found." is the same for you as for us, but I'm tempted to say it is.
We do not use SET CLASSLIB at all, we use newobject() instead of createobject(), but I think that, when the error occured, it coldn't be fixed even if I suspended the exe and issued a SET CLASSLIB.

>Doru,
>
>Thanks for the feedback.
>
>I have read both threads already, but I wasn't sure they were exactly the same problem I'm running into, for a couple of reasons.
>
>1. There is only one application and all the classes are members of it.
>
>2. This problem is intermittent, it's not isolated to a certain installation or process, it occurs randomly on different systems, when at other times the same process works fine on the very same system it failed on previously.
>
>Thanks again,
>
>- Aaron.