Pharmacy chain Walgreen Co suffered a system outage for several hours on Friday, taking all of its 8,200 pharmacy outlets offline and delaying prescription orders.
The company faced a "technical issue" during a system update and had to bring the entire system offline to resolve it, spokesman Michael Polzin said.
Some prescription orders may have been lost as a result of the outage, Polzin said, but most were queued and processed when the system was restored.
The pharmacy system was back online by 02:00 p.m. ET.
Shares of Walgreen closed at $61.05 on Friday on the New York Stock Exchange.
(This version of the story was corrected to say "orders may have been lost" from "orders were lost" in paragraph three.)
(Reporting by Ramkumar Iyer in Bangalore; Editing by Saumyadeb Chakrabarty)