This error is typically caused by evaluating special forms when the deliver keyword :keep-macros has been set to nil.
Beware of this when interacting with the debugger at delivery levels 2 and higher. The absence of the special forms quote and function can cause difficulty. You may find the functions find-symbol, symbol-function and funcall useful here. It may also help to keep the COMMON-LISP package (and perhaps also the SYSTEM package), or specific symbols (with the :keep-symbols keyword).
LispWorks Delivery User Guide - 10 Aug 2017