The owner of the BlackBerry smartphone says services have been restored worldwide after an embarrassing technical glitch left millions of users without e-mail and messaging for almost four days.
"All of the services are back up globally," Research in Motion (RIM) founder and co-chief executive Mike Lazaridis told a press conference. "We've now restored full services."
Lazaridis apologised to the millions of BlackBerry users in Europe, the Middle East, Africa, India, the US, Canada, Brazil, Argentina and Chile who were starved of instant access to e-mails and messaging since Monday.
Speaking on the fourth day of disruptions, which the firm blamed on a backlog of e-mails caused by an initial technical failure at a facility in Europe, Lazaridis said: "This was unfortunately the largest (outage) we've experienced."
RIM said an initial technical failure had prompted a build-up of messages in its network that snowballed around the world, affecting many of the firm's 70 million subscribers.
The hardware failure reportedly started at the company's British hub in Slough, a town west of London.
Lazaridis said the company was taking "immediate and aggressive steps", including with its suppliers responsible for the design and manufacture of the "core switch" blamed for the outage, "to minimise the risk of something of this magnitude happening again".
Its failure "caused a cascade failure in our system," he explained. "There was a back-up switch but the back-up didn't function as intended and this led to a backlog (of messages) in the system. The failure in Europe in turn overloaded systems elsewhere."
But Lazaridis conceded: "We (still) don't know why the switch failed in the particular way it did", and why the back-up system also failed.
RIM announced on Monday that the issue had been resolved, but the glitches spread, sparking outrage from BlackBerry users worldwide.
The problems represent a PR nightmare for RIM, which has faced weaker sales of the BlackBerry compared with smartphones made by Apple or those running Google's Android software. The timing is particularly bad ahead of Apple's launch on Friday of the latest version of its top-selling smartphone, the iPhone 4S, in key world markets.
Major Asia-Pacific markets such as Australia, Japan and South Korea have been unaffected for the most part, but irate users in China and India reported widespread outages this week.
Much of the anger has been caused by a lack of information about the problems, which Lazaridis acknowledged. In a video message earlier, he promised to update users more frequently through its websites and social media channels about future woes.
As a result of this week's outage, Lazaridis also said RIM is "very concerned" about the loss of customer confidence and sales.
