Out of Sync With Server Apex Legends Xbox Error: How to Fix the Problem
By Nathan Fusco

Out of sync with server Apex Legends Xbox error is a pesky bug plaguing players. The error can happen to PlayStation 4 or PC players as well, but seems to be more problematic on Xbox.
The error occurs after you log into the game, but try to connect to matchmaking. Sadly, the fix does take some time and patience and it doesn't always work.
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Out of Sync With Server Apex Legends Xbox Error: How to Fix the Problem
Here is how to fix the problem on the Xbox.
You need to open your ports and connect with the Xbox Live service. That means you'll need a configuration change to your firewall or network hardware, such as a router.
Here is the list of ports to open:
If this doesn't work, try looking for game service with Respawn Entertainment to see if it's on their side. You can always reset your modem and router as well and see if that helps with connection.
Photo courtesy of Respawn Entertainment