Previous studies (Cosmides, 1989, Cosmides & Tooby, 1989) have shown the Cheater Detection Module (CDM) to be an adaptive heuristic within social environments, and how it can improve human reasoning in many social exchange contexts. The purpose of this study is to examine the effects of the CDM on problem solving. To that aim, the ‘30 dollar room’ problem (Isaak & Just, 1992) is employed, which involves a social exchange context. Generally speaking, we use heuristics to efficiently solve normal problems. However, this particular problem can be considered to be a typical insight problem. While heuristics can function effectively in practical contexts, they can be obstacles to solving insight problems (Knoblich, 1999; Hiraki & Suzuki, 1998). We hypothesize that the CDM will make it difficult to find the correct answer for this insight problem. In order to investigate this hypothesis, we compare solution rates for the standard ‘30 dollar room’ problem with isomorphic problems that do not involve ‘social exchange’ contexts. The results indicate that the solution rates for the isomorphic problems were higher than for the standard version of the problem. The results are supportive of our hypothesis. The results indicate that there are situations in which the CDM, a cognitive system that has emerged in adaptation to social environments, has a negative influence as a cognitive constraint.