The time I've seen issues like this is when my launch point object or attribute is invalid. For example, if I had an attribute called WORKORDER.CUSTOMFIELD and I had an automation script on that attribute and later decided to remove the attribute, that is when I saw the error. I would look for situations like that where you don't see something in the MAXOBJECT and/or MAXATTRIBUTE tables.
If that doesn't help, if you can share the relevant stack trace I can try to correlate it more specifically.
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Steven Shull
IBM
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