Sims 4 Mod Checker: Find Broken Mods After a Patch (2026)

The 5-step mod check after every patch

Every game update turns your mods off. EA does this on purpose, because a mod that worked before the patch can break after it. Run this check before you turn them back on.

Back up your saves. Copy the Saves folder from Documents\Electronic Arts\The Sims 4\ (Windows) or ~/Documents/Electronic Arts/The Sims 4/ (Mac) to your desktop.
Test the game without mods. Launch with mods still disabled, load your save and play a few minutes in Live Mode. Then exit without saving (Menu, Exit Game, Exit Game again). EA warns that saving here can strip custom content from the save.
Check the broken mods list. Open the current Broken and Updated Sims 4 Mods and CC thread on EA Forums (linked from the board's START HERE post) and look up every script mod you use. Download fresh copies of anything marked updated; pull anything marked broken.
Turn mods back on. Game Options > Other > tick Enable Custom Content and Mods and, for script mods, Script Mods Allowed. Apply, quit and relaunch.
Let Better Exceptions watch. With BE installed, play normally. Any exception, UI error or CAS glitch produces a report that names the likely mod file. If something feels wrong but BE stays quiet, go to the 50/50 method below.

Your game version is shown in the lower left of the Main Menu. Note it down: creators and the broken mods list both refer to patch numbers.

Sims 4 mod checker tools compared

Most "mod checkers" do one narrow job. This is what each tool actually checks, verified against its own download page in November 2026.

Tool	Made by	What it checks	Platform	Status
Better Exceptions	TwistedMexi	Game exceptions, UI exceptions and CAS CC glitches in real time, with the responsible mod file in most cases; a conflict scan; Locate Outfit CC for glitched Sims	In-game script mod (PC and Mac)	Active. CurseForge lists v3.16 (Feb 23, 2026); v3.17 is in early access on TwistedMexi's site
CurseForge app	Overwolf (EA's official mod partner)	Shows an orange Update button when a mod installed through the app has a newer version	Windows, Mac	Active. Mods you installed by hand show a folder icon and cannot be updated by the app
Sims 4 Mod Manager	GameTimeDev	Organizes the Mods folder, enables and disables files so you can test, opens files in Sims 4 Studio	Desktop app	Active
Sims 4 Studio Batch Fixes	Sims 4 Studio team	Updates older CC for later game changes (Tools > Content Management > Batch Fixes)	Windows, Mac	Active
Mod Conflict Detector	DmitryMalfatto	Duplicates, non-Sims 4 files, stray files	Windows only	Abandoned since March 2018 (v2.2.300); the author stopped development

None of these reads a mod and tells you "this file is outdated for patch 1.129". Only the creator and the broken mods list can tell you that. A checker tells you which file is throwing errors, which is the next best thing.

How to use the broken and updated mods list

The EA Forums Mods and CC board keeps one running thread per patch, titled Broken and Updated Sims 4 Mods and CC. The current one at the time of writing covers patch 1.129 (October 27, 2026). Creators post there when they have tested or updated their mods, so the list fills in over the days after a patch.

Updated: the creator released a new version. Delete the old files and install the new download; a mod may need a full reinstall.
Cleared / no update needed: the creator tested it on the new patch.
Broken: remove it until the creator posts a fix.
Obsolete or no longer supported: the patch fixed what it did, or the creator retired it. Remove it.

The list is not complete. Thousands of mods exist and only some creators report. If a mod is missing, check the creator's own page (Patreon, CurseForge, Tumblr or Mod The Sims) for a note about the current game version. A mod marked fine for 1.128 is not automatically fine for 1.129.

Script mods (files ending in .ts4script) break far more often than CAS and Build/Buy CC (.package files). EA's own advice is to suspect gameplay mods before custom content.

Better Exceptions: the closest thing to an automatic mod checker

Better Exceptions (BE) is a free script mod by TwistedMexi. It takes the game's three error types (exceptions, UI exceptions and CAS CC glitches), tracks them automatically and in most cases names the mod file responsible.

Install

Download it from TwistedMexi's mods page (links to the free Patreon post) or from CurseForge. Avoid other sites: old versions circulate.
Put the .ts4script file in your Mods folder, at most one subfolder deep.
Enable Script Mods Allowed in Game Options > Other, then restart.

Use it

Errors: when a game or UI exception happens, BE reports it in real time. The report points at the file to update or remove.
Glitched outfits: type testingcheats true in the cheat console, Shift+click the Sim and choose Locate Outfit CC. BE lists every CC file in the current outfit.
Conflicts: open the BE menu from the welcome notification when you load a household and choose Check for Conflicts. The scan takes several minutes and opens a report in your browser.

Before you trust BE after a new patch, check its download page for the game version it was built for. On CurseForge, v3.16 was listed for game version 1.121.

The 50/50 method when no tool finds it

This is EA's own method, and it finds anything, including problems no checker reports.

Move the whole Mods folder to your desktop. Delete localthumbcache.package from the The Sims 4 folder (it is a cache; the game rebuilds it).
Move script and gameplay mods first. If the problem goes away when only CC is installed, the cause is a gameplay mod.
Put half of your mods back. Launch and test the problem.
Problem gone: the bad file is in the half still on your desktop. Problem back: it is in the half you just added.
Keep halving the suspect group, deleting the cache each round, until one file is left.

With 1,000 files this takes about ten rounds. Test in a new save or exit without saving so the testing does not change your real save.

Mod error codes and what they mean

Sign	What it usually means	What to check
Error code 102, 123, 125, 127, 129 or 131	A problem in the game's script; a script mod is a likely cause	Your `.ts4script` mods, newest patch first
Error code 110	Outdated mods, usually right after a game update	The broken mods list for the current patch
"Last Exception" pop-up or new `lastException` files	A logged script error	Read it with Better Exceptions; the files in the `The Sims 4` folder are logs and safe to delete
Hat floating above a Sim, stretched hair, missing body parts	A broken CC item	Locate Outfit CC in Better Exceptions
Sims walking up walls, eating for hours, menus not opening	A gameplay mod misbehaving	The mod that adds that menu or behavior

Mods not working? Fixes

Mods were fine yesterday, gone today. A patch turned them off. Game Options > Other > Enable Custom Content and Mods, then restart.
Package CC loads, script mods do not. Tick Script Mods Allowed. Keep .ts4script files no more than one folder below Mods (Mods\Creator\ works, Mods\Creator\Mod\ does not). Keep a mod's script and package files together.
Download did nothing. Unzip it. The game loads .package and .ts4script files, not the .zip you downloaded.
Mod updated but still broken. Delete every old file of that mod first, then install the new version. Delete localthumbcache.package.
CurseForge says nothing to update. The app only updates mods installed through it. Hand-installed mods need a manual check.
Mac. Use ~/Documents/Electronic Arts/The Sims 4/Mods. In the CurseForge app, point it at the folder that contains The Sims 4.app.
PlayStation and Xbox. Console versions do not support mods, so there is nothing to check.

Tired of re-checking mods after every patch?

Patch day means a stack of disabled mods, a forum list to read and an evening of 50/50 testing. If you want a life sim with nothing to install and nothing to break, LifeSim is a free online life simulator that runs in your browser on a computer or phone. There is no download and no packs to buy. You can be anyone in any real city on Earth and live a life day by day, with needs, a job, relationships and AI-driven townspeople. Play it while your creators catch up with the patch.

Safety notes

Download mods only from the creator's own page or CurseForge. Maxis and EA do not screen or support mods.
Mod The Sims accounts have been compromised before and used to upload malicious files. TwistedMexi's free ModGuard blocks and warns about known compromised mods.
Be wary of new "mod manager" or "mod fixer" programs from people with no Sims 4 history. The broken mods list thread itself warns about these and notes that none of them are necessary.
Delete localthumbcache.package after any mod change. Never delete your Saves or Tray folders while testing.

FAQ

Is there an official Sims 4 mod checker?

No. EA turns mods off after each update and tells you to check with creators. The game shows a list of installed mods at startup, but it does not say which ones are outdated.

Does Better Exceptions find outdated mods?

It finds mods that throw errors, which is how most outdated script mods show up. A mod that is outdated but quiet will not appear, so still check the broken mods list.

Can the CurseForge app tell me which mods are broken?

It shows updates for mods installed through the app. It cannot update or check mods you installed by hand.

Is it safe to delete lastException files?

Yes. They are log files. Deleting them does not fix the cause, so read them first or let Better Exceptions explain them.

Can I check mods on PS5 or Xbox?

The Sims 4 on console does not support mods, so there is nothing to check.

Sims 4 Mod Checker: How to Find Broken Mods