Project Zomboid B42 — Server Fails to Start (Out of Memory)

The Problem

On Project Zomboid Build 42 (B42), dedicated servers may fail to start with a Java Memory Error during startup. This is not caused by corruption or mods — it happens because the default Java heap allocation is too aggressive for the server resources available.

Who Is Affected

• Project Zomboid Build 42 servers
• Servers with 8 GB RAM or less

B42 has significantly higher memory requirements than B41 due to expanded world generation and new game systems. Servers with less than 6 GB RAM may struggle even with optimized settings.

How to Fix - Edit Configuration File

1. Go to the Files tab in your panel
2. Open ProjectZomboid64.json in your server root folder
3. Find the line "-Xmx8g"
4. Change it to a lower value (see table below)
5. Save and restart the server

Note: On some Pterodactyl eggs, this file may be overwritten on restart. If your changes do not persist, use the Startup variable method or contact support.

Recommended Memory Values

The value should always be lower than your total server RAM to leave room for the operating system and other processes.

Still Crashing?

• If the server starts but crashes after running for a while, your server may need more RAM for your world size and mod count
• Remove unnecessary mods to reduce memory usage
• If you have optimized settings and are still hitting limits, consider upgrading your plan