Need a Minecraft server? BeastNode offers the highest performance servers with DDoS protection!

Shop for plans now

Failed to check session lock

Failed to check session lock errors can occur randomly and usually begin with this line:
net.minecraft.server.WorldConlictException: Failed to check session lock, aborting

It will cause your server to crash. The fix for this is to simply navigate to your world folders and delete the session.lock files in them, then restart your server.

  • 43 Users Found This Useful
Was this answer helpful?

Related Articles

Server Not Starting - "Caused by: com.google.gson.stream.MalformedJsonException"

With the update to UUID's in 1.7.9, Minecraft also updated the file formats used for the OPs,...

Failed to Adapt Server Configuration

If you are getting the "Failed to adapt server configuration" error in your console when starting...

Whitelist enabled in the server.properties but not working

This is caused if the whitelist.json file format is broken. Whilst the other .json files will...

NukkitX - No Mobs Spawning

This is a known/reported issue for NukkitX and has been for a while now. Unfortunately there...

Poor Performance/Lag (MineCraft 1.14.*)

This is unfortunately an issue with the Minecraft 1.14.* releases themselves and isn't something...