The systems have been on shut down since Monday and efforts are on to resolve the issue, OIL spokesperson Tridiv Hazarika said.
“We have been forced to withdraw all our computer system from LAN connection after it came to our knowledge that three to four computers were hit by a virus Monday.”
No computer at the headquarter now has access to internet connectivity, he said.
“The IT department is yet to ascertain the extent of damage. OIL is working on solving the issue. Previously too OIL faced such problems, but this time it seems to be a major IT-related crisis which will take time to resolve,” Hazarika added.