Mailbox, the new email app for iPhone app that reviewers went nuts over last week, is experiencing problems delivering messages to users.
Right now, Mailbox will display a badge notification on the app icon when you get a new email, but the messages won't load when you open the app.
We've reached out to Mailbox for comment, but the company has responded to several customer complaints on Twitter saying there's "an unusual server issue."
It's unclear how many users are affected, but we're getting an error message that says, "having trouble connecting. Please, try again soon." We've also seen several complaints from Mailbox users on Twitter.
Mailbox is going through a phased rollout with a reservation system in an effort to keep the company's servers from becoming overloaded. Users have to fill out a form online and enter a unique code to get in line for the app.
Reservations are filled first come, first serve, but there are currently hundreds of thousands of people waiting for access to Mailbox.
UPDATE 5:40 p.m. Eastern: It's back! After several hours of downtime, Mailbox is working again.
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