Apple's main website for developers remains shut after intruders tried to steal sensitive information last week, forcing the iPhone maker to overhaul its database and server software to prevent future breaches.
The intrusion last Thursday marked a rare cyber attack on the U.S. company's network and comes at a time when third-party developers are testing their apps on Apple's iOS 7 - a smartphone and tablet platform to be launched in the fall.
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Apple's developer site also houses sensitive financial information, which is encrypted.
Apple said on Sunday that no customer information had been compromised, but was unable to rule out the possibility that some developers' names, mailing addresses, and email addresses may have been accessed.