A fascinating case study. The usual advice is to keep backups and practise restoration on a regular basis. With industrial systems this isn’t always feasible. Thank goodness for the store cupboard full of ancient kit…:
[…] Some 35,000 employees were locked out of the company’s network, and Hydro had to shut down several manufacturing plants in Europe and the U.S. The ones still operating had to figure out how to do so without any computers. In the end, the attack would cost the company more than $60 million—way more than the $3.6 million the insurance policy has paid out so far, according to an earnings report.