(Reuters) – 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. Shares of Walgreen closed at $61.05 on Friday on the New York Stock Exchange.