The 180-year-old Brunton Dairy in Beaver County voluntarily stopped bottling milk from July 30 to Oct. 1 after state health and agriculture officials found the bacteria.
The dairy began bottling and selling milk again, only to stop producing milk Oct. 25. State agriculture officials now said a bacteria test that prompted the second shutdown was the result of a laboratory error.
Two people who claimed to be sickened have sued the dairy.
Herb Brunton, a partner in the dairy, said it's too soon to say when the dairy may resume home deliveries to 1,000 customers or sales through 25 retail outlets.