This paper presents a measurement-based analysis of the fault and error sensitivities of dynamic memory. We extend a software-implemented fault injector to support datatype-aware fault injection into dynamic memory. The results indicate that dynamic memory exhibits about 18 times higher fault sensitivity than static memory, mainly because of the higher activation rate. Furthermore, we show that errors in a large portion of static and dynamic memory space are recoverable by simple software techniques (e.g., reloading data from a disk). The recoverable data include pages filled with identical values (e.g., '0') and pages loaded from files unmodified during the computation. Consequently, the selection of targets for protection should be based on knowledge of recoverability rather than on error sensitivity alone.