Perhaps the difference is whether or not you've opened the class in memory (by editing it, say) and not. In which case you might just need to add a SET CLASSLIB command in your forms.

>I have a program that defines two classes. I run the program, then try to create an object based on the second class. Sometimes it works fine, but more often it tells me it can't find the class. I don't see anything different between what I do when it works and when it doesn't work. I've never had any trouble with the first class.
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