Summary Box: BlackBerry service restored

THE DEVELOPMENT: BlackBerry services buzzed back to life across the world after a three-day outage that interrupted email messages and Internet services for millions of customers.

PROBLEM SOLVED: Research In Motion Ltd., which makes the phones and handles email traffic to them, said the system was steadily processing a vast backlog of stalled messages. A crucial link in BlackBerry’s European network had failed Monday, and a backup also failed.

POSSIBLE FALLOUT: One looming question is whether more businesses and consumers will abandon the BlackBerry, already facing fierce competition from the iPhone and phones running Google’s Android system.