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My old modem was malfunctioning and I had to get a new one. However, now my girls can't join each other's games in Minecraft PE. Their iPods are both connected to the new wifi and they can sync apps. It is only in Minecraft PE that they get the message "Server Outdated" or "Outdated Client". They spent a lot of time creating some of these worlds and are pretty devastated that they can't join together. Any ideas?