BlackBerry services are returning to normal in Europe, the Middle East, India and Africa, Research In Motion said in the early hours of Thursday morning.
At around 5:30am BST, RIM said it was seeing "a significant increase in service levels" in the regions, after a spell of downtime that began on Monday morning. BlackBerry problems in the US, Canada and Latin America also appear to be clearing up, and RIM said it was "seeing increased traffic throughput on most services, although there are still some delays and services levels may still vary amongst customers".
The update came hours after RIM held a press conference and issued a statement on Wednesday evening. "We believe we understand why this happened," RIM chief information officer Robin Bienfait said. "We are working to restore normal service levels in all markets as quickly as we can."
The problem appears to have begun with the failure of a core switch in RIM's infrastructure. The system failed to fail back to a backup switch, and emails and instant messages began piling up. Because all internet traffic generated by BlackBerry devices is routed through RIM's servers for encryption and data optimisation purposes, most BlackBerry internet services fell victim to this blockage, and the problem eventually spread from the EMEA region to other parts of the world.
As of RIM's second-to-last update at 11:44pm BST on Wednesday, the situation was as follows. In Europe, the Middle East, India and Africa (EMEIA), email systems were back up and running, although RIM was still working through a backlog of messages. BBM messaging services were running smoothly, but browsing was temporarily unavailable.
In Canada, the US and Latin America, email was functional but the backlog was still being cleared. BBM and browsing were operational for everyone except customers of three Latin America operators, who RIM said were "services by the EMEIA infrastructure". RIM added that it was investigating reports of BBM delays.
"You've depended on us for reliable, real-time communications, and right now we're letting you down," Bienfait said. "We are taking this very seriously and have people around the world working around the clock to address this situation."
During the press conference, RIM said it would not yet contemplate compensation for those affected by the lengthy outage, as it was first concentrating on getting its systems back to normal.
UPDATE (8:44am BST): RIM has just issued a statement reading: "From 6am BST today, all services across Europe, the Middle East and Africa, as well as India, have been operating with significant improvement. We continue to monitor the situation 24x7 to ensure ongoing stability. Thank you for your patience."