...All of the departments did not file a report may mean that some departments did not file, or that none did. The first meaning can be expressed unambiguously by the sentence Not all of the departments filed a report. The second meaning requires a paraphrase such as None of the departments filed a report or All of the departments failed to file a report. The same problem can arise with other universal terms such as every in negated sentences, as in the ambiguous Every department did not file a report....