Microsoft claims to have fixed a problem with its Hotmail service in which 18,000 users lost their messages.
The affected users found that many of their messages had been deleted last week, raising concerns about the resilience of third-party cloud-based applications as well as the wisdom of using personal email accounts for important business correspondence.
"Beginning on 30 December we had an issue with Windows Live Hotmail that impacted 17,355 accounts," said Chris Jones, from the Windows Live team, in a blog post.
"Customers impacted temporarily lost the contents of their mailbox through the course of mailbox load balancing between servers. We identified the root cause and restored mail to the impacted accounts as of 2 January."
Jones added that Microsoft will investigate the cause of the outage and will take steps to ensure that it does not happen again.
However, comments below the blog post suggest that some users are still without their emails, and that many are worried about the integrity of the service.
"My inbox of over 8,000 emails from the start of this address over 10 years ago is still gone," wrote one user, who complained that Microsoft support had been lacking.
Another added damningly: "Having read 482 pages of the Windows Live Solution Center posts, is it not time to close this thing down or rename it? It is very far from being 'live' and completely useless for 'solutions'."
A forum on Microsoft's Windows Live Solution Center help pages relating to the matter has been locked and marked as resolved, and Microsoft appears to be fixing user accounts on a person-by-person basis.
Anyone still having a problem with their account is urged to visit a separate Windows Live help page and fill out a detailed report.
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