As of October 23, 2026, with Stardew Valley on 1.6.15 and SMAPI on 4.5.2, almost every «my mods aren’t working» case comes down to four checks: the game is really launching through SMAPI, the game, SMAPI and your mods are all up to date, every mod has its dependencies, and each one is placed correctly in the Mods folder. If the game crashes, the SMAPI log (SMAPI-crash.txt or SMAPI-latest.txt) tells you which mod is failing; if that isn’t clear, disable mods in halves by putting a dot in front of their folder name.
Quick diagnosis
| Symptom | Likely cause | What to do |
|---|---|---|
| No mod does anything and the SMAPI console doesn’t open | The game is launching without SMAPI | Check your Steam launch options or open StardewModdingAPI |
| A mod shows up under «Skipped mods» | It’s missing a dependency or needs a different version | Install whatever the reason in the log points to |
| A content pack ([CP]) doesn’t change anything | Its framework is missing, such as Content Patcher | Install it and check that it loads without errors |
| Everything stopped working after a game update | Outdated SMAPI or mods | Reinstall SMAPI and update your mods |
| The game crashes when loading your save | A broken content mod, or one that was only partly removed | Read SMAPI-crash.txt and isolate the mod |
| Repeated red messages in the console | A mod keeps failing throughout the game | Update it or remove it |
For each specific SMAPI message (manifest.json, antivirus, «Could not load file or assembly»…), you’ll find a detailed explanation in our guide to SMAPI errors. Here we stick to the practical part: how to find the culprit.
Step 1: confirm the game launches with SMAPI
It’s the simplest and most common problem: the game starts as usual, without SMAPI, so the mods do nothing. With SMAPI, a console window opens next to the game and lists the loaded mods. If you don’t see it:
- Windows with Steam: the game’s launch options must be the ones the SMAPI installer gave you, in the format
"…\Stardew Valley\StardewModdingAPI.exe" %command%. - Linux, macOS and native Steam Deck: leave the launch options empty.
- After a game update: if the SMAPI window stopped appearing, run the installer again.
Step 2: game, SMAPI and mod versions
SMAPI 4.5.2 needs Stardew Valley 1.6.14 or later, and many current mods already require 1.6.15: Content Patcher 2.9.1 and SpaceCore both need that version. The game version shows on the title screen when you press «?», and the SMAPI version on the first line of its console. On startup, SMAPI also tells you which mods have a new version: the wiki recommends updating all of them, even if they seem to work. If you play on Steam, also make sure you’re not on a beta branch that SMAPI doesn’t support.
Step 3: read the SMAPI log
SMAPI saves each session to a text file. If the game crashed suddenly, open SMAPI-crash.txt; if it doesn’t exist, SMAPI-latest.txt. You’ll find them in:
- Windows (Steam or GOG): %appdata%\StardewValley\ErrorLogs
- Linux, macOS and Steam Deck: ~/.config/StardewValley/ErrorLogs
At the end of loading, SMAPI lists the «Skipped mods» with the reason next to each one: almost always a missing dependency or a minimum version. If you ask for help, upload the file to the smapi.io/log parser and share the link it gives you.
Step 4: isolate the broken mod (split in half)
- Copy your saves folder: %appdata%\StardewValley\Saves on Windows or ~/.config/StardewValley/Saves on Linux, macOS and Steam Deck.
- In the Mods folder, disable half of your mods by putting a dot in front of their folder name (for example, .LookupAnything). SMAPI ignores those folders.
- Launch the game. If the problem is still there, the culprit is among the active mods; if it’s gone, it’s among the ones you disabled.
- Split the suspect group in half again and repeat until you’re down to one mod.
Two tips: disable mods together with the ones that depend on them (if you remove Content Patcher, every [CP] pack stops loading and the log fills up with warnings), and test on a new save first. Be careful with expansions: Stardew Valley Expanded and similar mods add maps, characters and items, and removing them from a save in progress can cause problems. That’s why backing up your saves comes first.
Other common causes
- Folder extracted the wrong way. Each mod goes in its own folder, with its manifest.json. If extracting leaves you a folder with numbers (ModName-1234-1-0), move the mod’s actual folder into Mods.
- Mods that aren’t SMAPI mods. Some old mods replace the game’s .xnb files and don’t go in Mods. Follow the author’s instructions.
- Two versions of the same mod. SMAPI won’t load duplicates: keep only the newest one.
- Steam Deck with Proton. If you see «The library ‘libhostpolicy.so’ required to execute the application was not found», you have the Linux SMAPI with the Windows version of the game.
More Stardew Valley guides: how to install mods, SMAPI errors, expansion mods and mods in multiplayer.
Frequently asked questions
Why don’t my Stardew Valley mods do anything?
Most likely the game isn’t launching with SMAPI. If its console window doesn’t open, check your Steam launch options or run the installer again.
How do I disable a mod without deleting it?
Put a dot in front of its folder name inside Mods. SMAPI ignores it; remove the dot to turn it back on.
Where is the SMAPI log?
In %appdata%\StardewValley\ErrorLogs on Windows and in ~/.config/StardewValley/ErrorLogs on Linux, macOS and Steam Deck. Use SMAPI-crash.txt if the game crashed.
What do I do if a mod appears under «Skipped mods»?
Read the reason SMAPI gives next to it: it’s usually a missing dependency or a minimum version of the game or SMAPI. Install or update whatever it asks for.
Can I remove a mod in the middle of a save?
Interface and quality-of-life mods, usually yes. Mods that add content (items, maps, characters) can leave your save with problems: back it up first.