Files with the .DMP extension contain data that has been dropped from the memory taken up by an application in the Windows system and then saved on the disc, usually during a software crash or after a system reboot after a crash, by the Savedump.exe software.

Memory drop files are usually named Memory.DMP and are used for resolving system errors, as well as diagnosing their causes. Since the system and the applications can take up a lot of memory, DMP files can also be very large – sometimes almost as large as the computer’s entire internal memory.