Analysis and optimization of the curing process of epoxy resins can be easily carried out using differential scanning calorimetry. Presented here is a measurement on a glass fiber filled epoxy measured in the DSC 200 F3 Maia®. The two-step exothermal cross-linking reaction slightly above the glass transition (at 101.5°C) is clearly visible during the first heating of the sample. After a controlled cooling at 5 K/min, the sample was heated a second time. Only a weak glass transition is visible at a higher temperature (142.4°C) compared to the first heating cycle.