Connectivity Problem with Project Zomboid - File doesn’t exist for project zomboid version 42.13.1

Technical Support
,
1

OS Name/Version:
Ubuntu Server 24.04.3 LTS (x86_64)

Product Name/Version:
CubeCoders AMP 2.6.4.2 (Tools 2.6.3, Release Stream: Mainline)

Problem Description:
When hosting a Project Zomboid v42.13.1 multiplayer server using CubeCoders AMP, clients fail to connect with the error:

File doesn't exist on the client:
media/lua/shared/DAMN_BackCompat.lua

Key points:

  • The file does exist in the Steam Workshop directory on the client.

  • The same mod list works correctly when connecting to non-AMP servers.

  • The issue is not tied to a specific mod; fixing or removing one mod causes a similar error with another.

  • This only happens on servers hosted via AMP.

  • Strongly suggests a workshop/mod mounting or sync issue in AMP for Project Zomboid b42 MP.

Steps to reproduce:

Step 1
Install CubeCoders AMP on Ubuntu Server 24.04.3

Step 2
Create a Project Zomboid server instance targeting Build 42.13.1 MP

Step 3
Configure the server with a verified, b42.13-compatible mod list (Mods + WorkshopItems)

Step 4
Start the server and attempt to connect from a Steam client with all mods installed

Step 5
Client fails to connect with “File doesn’t exist on the client” Lua errors

Actions taken to resolve so far:

  • Fully deleted and reinstalled the AMP Project Zomboid instance

  • Verified Workshop downloads and mod integrity

  • Reordered mods (frameworks first)

  • Confirmed mod compatibility with b42.13 MP

  • Tested the same mod list on non-AMP servers (works correctly)

Result:
Issue persists only on AMP-hosted servers.

2

Despre si ai invedre bun?

3

Given that PZ manages mods all by itself, and AMP has nothing to do with it, you’d have to show how you’ve configured the settings in AMP

4

After adding the mods, deleting the workshop-save-db folders and leaving only the configuration ini files, then restarting the server, the mods work without any problems.

I never had this problem in B41, no matter how many mods I added or removed.

5

b42 is an experimental build atm (and .13 is a bleeding edge version of that), so expect issues

6

Oh, and your ampinstmgr is quite out of date. You need to update it: (as root) getamp update

7

i have similar issue, could you tell me more about it?

i cannot find workshop-save-db folder on my amp server

8

They are talking about the individual folders Zomboid/db, Zomboid/Saves, Zomboid/Workshop

B41 dbs are not compatible with b42, so that is likely what is causing the issue

9

I had the same Problem with every mod i installed on my server and i fixed it by activate the Automatically Whitelist Players option in the Project Zomboid→Server options in the instance configuration.

edit: I also disabled “Enable Lua Checksum Kick