How to Find Which Mod Causes Errors in Project Zomboid

Project Zomboid Build 42.19: back up the save, capture a clean log, map the first stack clue, then disable the bad mod.

Do not delete your whole Zomboid user folder That directory holds saves, multiplayer data, hosted-server configs, options, local mods, and the logs you need. Back up the affected save (or the full folder), then rename or move logs—never wipe the original directory as a “clean install” step.

Mods can throw Lua/Java exceptions, break load order, or leave a save unplayable. Protect the save first, capture one clean failure, read the first relevant stack trace, map file names or Workshop IDs to a mod, disable that mod on the save, and only then half-search remaining suspects.

For crashes, lag, and non-mod failures, see How to Fix Project Zomboid Errors, Crashes, Issues, Lag.

Zomboid Error Mod Finder

Paste console.txt (or a relevant chunk from Logs/ / logs.zip). The tool stays in your browser, highlights the first strong error, and lists Workshop IDs, Lua/script paths, and other mod-like clues so you know what to search next.

Log content

Privacy: nothing is uploaded. Before sharing logs publicly, remove passwords, IPs, Steam IDs, tokens, and private chat.

1. Back up the save—not a destructive “reset”

Preferred backup Close the game completely. Copy the specific save folder under Saves (and the full Zomboid folder if you want maximum safety). Keep the original directory in place.

Quit Project Zomboid so log and save files stop writing.
Copy the failing save directory to a dated backup location.
Optionally copy the entire Zomboid user-data folder as a second safety net.
Do not delete the original Zomboid folder after copying it.

Windows user data

%UserProfile%\Zomboid\
Saves: %UserProfile%\Zomboid\Saves\
Main log: %UserProfile%\Zomboid\console.txt
History: %UserProfile%\Zomboid\Logs\
Support zip when present: %UserProfile%\Zomboid\logs.zip
Local mods only: %UserProfile%\Zomboid\mods\

macOS and Linux user data

~/Zomboid/
Saves: ~/Zomboid/Saves/
Main log: ~/Zomboid/console.txt
History: ~/Zomboid/Logs/
Support zip when present: ~/Zomboid/logs.zip
Local mods only: ~/Zomboid/mods/

File explorer showing a Project Zomboid user-data folder being copied for backup — Copy the user-data or save folder to a backup location. Leave the original folder where it is.

Full backup steps: How to save and back up your game.

2. Capture one clean failure log

With the game closed, rename console.txt to something like console_old.txt (or move it aside). A new file will appear on the next launch.
Launch the game with the same mod set you need to diagnose.
Reproduce the problem once—same save action, same menu, same multiplayer step.
Quit cleanly, then open the new console.txt. Prefer this single-run log over an endless append of older noise.

Local mods ≠ Steam Workshop content Copying Zomboid/mods only covers manually installed / local mods. Subscribed Workshop mods live under Steam’s workshop/content/108600 tree. You do not need to delete or “rebuild” Workshop folders just to get a clean log.

3. Read the first relevant error, not the last noise

Search near the end of the failing run for the first strong signal: ERROR, Exception, Caused by, stack traceback, a .lua path, a Workshop numeric ID, or a named mod folder. Later lines often only report fallout from that first failure.

Windows PowerShell:

Select-String -Path "$env:USERPROFILE\Zomboid\console.txt" -Pattern "ERROR|Exception|Caused by|stack traceback|media/lua|workshop|mod"

macOS or Linux:

grep -niE "ERROR|Exception|Caused by|stack traceback|media/lua|workshop|mod" ~/Zomboid/console.txt

Clue in the log	What it usually means	Next action
Path under `workshop/content/108600/<digits>/`	A subscribed Workshop item is named by that numeric ID	Open that ID folder; read `mod.info` / folder name; disable the matching mod on the save
`media/lua/...` or `.lua` file in a stack trace	A Lua script failed during load or runtime	Search that file name under Workshop `108600` and under `Zomboid/mods`
Mod display name or short mod ID fragment	The game already printed a human-readable or partial mod id	Match it in the save’s Mods list (Load → More → Mods) and disable it
Only vanilla game paths, no Workshop path	May be base game, corrupted install, or a mod that rewrote shared code without a clear path	Verify game files; if the error only appears with mods on, binary-search the save’s mod list
Checksum / Workshop version mismatch text	Client and server (or two clients) do not share the same mod build	Align Workshop subscriptions and restart the outdated side before hunting Lua stack traces

Example Project Zomboid console log lines showing error text — Start from the first ERROR / Exception for this run, then read the stack lines immediately under it.

4. Map the clue to a Workshop or local mod folder

Steam Workshop content (subscribed mods)

Windows (typical): C:\Program Files (x86)\Steam\steamapps\workshop\content\108600\
macOS: ~/Library/Application Support/Steam/steamapps/workshop/content/108600/
Linux: ~/.steam/steam/steamapps/workshop/content/108600/ (or your Steam library’s steamapps/workshop/content/108600/)

Local / manual mods

Windows: %UserProfile%\Zomboid\mods\
macOS / Linux: ~/Zomboid/mods/
These are separate from Workshop IDs under 108600

Copy a distinctive file name from the stack (for example a .lua path segment).
Search inside the 108600 workshop folder and, if needed, inside Zomboid/mods.
When you find the file, open its parent mod folder. The folder under 108600 is the Workshop item ID; the mod’s own folder and mod.info give the in-game mod id/name.
If nothing matches, treat it as “unknown mod or base game” and use binary disable (next section).

Steam workshop content folder for Project Zomboid app ID 108600 — Workshop downloads for Project Zomboid live under content ID 108600.

Search result highlighting a Lua file inside a Workshop mod folder — Search the exact file name from the stack trace to land inside the responsible mod package.

Address bar showing the Workshop mod folder path and mod name — The path under 108600 identifies the Workshop item; the inner folder and mod.info identify the mod itself.

Folder layout reference: Where Project Zomboid Workshop mod files are located.

5. Disable the bad mod on the save (and in the main list)

From the Load menu, open the save → More → Mods.
Disable the identified mod for that save. Also clear it from the main Mods list if it is enabled globally.
Load once and confirm the error is gone. If the save still fails, keep the log from this new run—another mod may be second in line.

Save-bound mod lists matter Disabling a mod only in the main menu is not enough if the save still enables it under More → Mods. Always check the save-specific list.

6. When the log is unclear: binary-search the mod list

Random one-by-one disable is slow and easy to mis-order. Use half-sets after a known-good baseline:

Confirm the save loads with all mods disabled (or with only mods you must keep for that save format).
Enable half of the previous mod list. Load once and reproduce the action.
If the error returns, the culprit is in that half. If not, it is in the other half (or in a dependency of the first half).
Repeat on the failing half until one mod (or a small conflicting pair) remains.
Retest the suspect alone, then with likely dependency partners (map frameworks, library mods, collection packs).

Keep notes each pass

Which half was enabled
Whether the error reproduced
The first new ERROR line

Watch for dependency traps

A “library” mod may not crash alone
Two mods can only fail together
Map packs often need their framework mods

Search UI showing no matching file for a log path — If the file is not under Workshop or local mods, switch to binary disable and verify base game files.

7. Controlled checklist

Failing save (or full Zomboid folder) is backed up outside the live directory.
You did not delete the original user-data folder.
You captured a single reproduction in a fresh console.txt.
You recorded the first strong ERROR / Exception and any Workshop ID or Lua path.
You searched both 108600 Workshop content and Zomboid/mods.
You disabled suspects on the save Mods list, not only the main menu.
If sharing logs, remove personal identifiers first.

How to Find Which Mod Causes Errors in Project Zomboid

Zomboid Error Mod Finder

1. Back up the save—not a destructive “reset”

Windows user data

macOS and Linux user data

2. Capture one clean failure log

3. Read the first relevant error, not the last noise

4. Map the clue to a Workshop or local mod folder

Steam Workshop content (subscribed mods)

Local / manual mods

5. Disable the bad mod on the save (and in the main list)

6. When the log is unclear: binary-search the mod list

Keep notes each pass

Watch for dependency traps

7. Controlled checklist

Related guides

Related Articles