Did you download the latest version from solemma.com? I am suspecting that this is related to some incompatibilities between ETO froms dlls.
Could you send us a screenshot of your installation folder C/DIVA/64BitPluginfiles?
I have uninstalled and reinstalled DIVA, but the folder structure looks like still as in the previous image. I' ve tried to move all files from the ArchSim folder, but the result is the same.
Please try the latest installer online. This should fix this issue.