The problem, which has left subscribers with limited access to BlackBerry's services since Monday, has now spread to between 30 million and 40 million users. Robin Bienfait, RIM chief information officer, said it was working "around the clock" to fix the problem.
He added: "You’ve depended on us for reliable, real-time communications, and right now we're letting you down."
The problem began after a core switch failure within RIM’s infrastructure. A back-up switch failed to work despite being previously tested and, as a result, a large backlog of data was created that the company is still trying to clear.
The switch failure occurred at a data centre in Slough and caused problems in Europe, the Middle East and Africa, before spreading to other regions including India and America.
At a press conference last night, Bienfait was forced to deny the problems were the results of hacking.
Rumours of hacking have coincided with Sony's announcement that its PlayStaion network had fallen victim to another hack, which has forced the company to freeze the accounts of 90,000 users.
The problems affecting BlackBerry have come as RIM struggles to maintain market share against smartphone rival Apple and handset makers using Google’s increasingly popular Android operating system.
Apple is looking to steal another march on the market with the release of its new operating system iOS 5, which is now available for download.
RIM claimed that from 6am today (13 October) "all services across Europe, the Middle East and Africa, as well as India, have been operating with significant improvement".
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