People who rely on Skype’s Windows desktop, iOS and Android apps should be aware that receiving a message of “http://:” (without the quotation marks) will cause the app to crash. When they try to restart the app, it will crash again on startup, locking them out of the service. If there’s a silver lining, Skype’s Mac app and Modern Windows app, which is available for download through the Windows Store, seem unaffected by the bug.

The problem was first spotted by users on Skype’s community support forums. According to a report by VentureBeat, a user who goes by the handle “Giperion” posted about the issue first, noting that deleting the chat history on a device didn’t help, because Skype would automatically download it again from the cloud after starting back up, and then promptly crash again. That thread has since been deleted for reasons that are unclear.
These 8 characters crash Skype and leave it unable to reopen | PCWorld