Dear Barry,

There is no way to recover unsaved development after a crash. You should be able to access the project files according to the last time you saved the project.

To avoid issues you can:

• Use the auto back functionality for data which will save your data at regular intervals if you configure it - https://documentation.aimms.com/user-guide/introduction-to-aimms/additional-files-related-to-an-aimms-project.html
• And the AutoSave functionality that will automatically save the project every X minutes - Menu → Settings → AutoSave and Backups → Project

We also recommend using version control to improve source code management.

Best regards,