OSLO, March 26 (Reuters) – Norwegian aluminium maker Norsk Hydro may have lost more than $40 million in the week that followed a ransomware cyber attack that paralysed parts of the company’s operations, it said on Tuesday. On a preliminary basis, the financial impact during the first week was estimated at between 300 million and 350 million Norwegian crowns ($35 million-$41 million). “Hydro has a solid cyber risk insurance policy with recognized insurers, with global insurer AIG as lead,” it added. The company did not say how much money it hoped to recover from its insurance. While Hydro’s primary metals business continues to produce aluminium, one of its key products unit still struggled to recover. “In the most affected business area, Extruded Solutions, production is now at 70-80 percent, except for the Building Systems business unit, where operations remain almost at a standstill,” Hydro said. The company has said it will not pay hackers to unlock its files, preferring instead to restore its files from backup servers. “The company has now entered the recovery phase following the attack, gradually restoring IT systems in a safe and secure manner to ensure progress toward normal business while limiting the impact for people, operations, customers, suppliers and other partners,” Hydro said.