Hi Martin,
I understand that you want to recover the data from a prior session using the “.DMR” file in the temporary folder.
These “. DMR” files are created by the SDI (Simulink Data Inspector) at 'C:\Users\username\AppData\Local\Temp\'. To get to the file path you can run the following command in MATLAB:
>> tempdir
>> Simulink.sdi.getSource %Return location for storing simulation data
Since, these files are stored in the backend for Simulink’s logging during the simulation and are automatically deleted once MATLAB closes, it is not intended or designed to be directly opened or accessed by the end user. And there is a high probability of the file being corrupted due to improper termination or crash.
You can also refer to the following MATLAB Answer which addresses the similar problem that you are facing:
Hope it helps,
Regards,
Ayush Misra
