This experiment tested the possibility that older adults are less susceptible to semantic illusions because they are more likely to notice contradictions with stored knowledge. Older and young adults encoded stories containing factual inaccuracies; critically, half the participants were instructed to mark any errors they noticed. Older adults reproduced fewer story-errors on a later general knowledge test, but there were no age differences in marking errors during encoding. However, older adults were better able to recover and answer correctly after failing to notice errors during story-reading. Implications for false memories and semantic illusions are discussed.