"The Danger/Microsoft team is continuing to work around the clock on the data restoration process," Microsoft said in a statement Sunday.
"We apologize that this is taking so long, but we want to make sure we are doing everything possible to maintain the integrity of your data," the company said.
Microsoft also issued a similar statement Saturday, noting that the team was "conducting its last round of rigorous tests before making the restoration process available to you." The company added that data restoration "is only necessary for customers who lost data from their Sidekick devices.
Microsoft said last week that it had recovered most of the data, such as contacts, calendar entries and other personal information, and that it would begin the restoration process as soon as possible.
The company said it believed data loss affected only a minority of Sidekick users, while various reports indicated that users who had reset their devices during, or just prior to, the outage were mostly likely to have been victimized by the problem.
A Microsoft executive said in a statement last week that the company, along with network partner T-Mobile, was taking steps to ensure that similar problems don't re-occur in the future.
"Specifically, we have made changes to the overall stability of the Sidekick service and initiated a more resilient backup process to ensure that the integrity of our database backups is maintained," said Roz Ho, Microsoft's VP for Premium Mobile Experiences.
The reassurance didn't satisfy all users, however. The incident has prompted at least one class-action lawsuit against Microsoft and T-Mobile, and more could be pending.
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