In this article we gathered a list of error messages that you may encounter when using the CurseForge app, and solutions that can help solve them.


Take me to...

General

An error has occurred. Please check your connection and try again.

Please make sure your network connection is working properly:

  1. Antivirus and other types of software

    If you're using an antivirus or other types of software that could affect your network connection, please disable them temporarily and check if there's any change with the issue.

  2. VPN

    Try to temporarily disable any VPN programs you have running, as they may interrupt the connection required for CurseForge to install the necessary Java or Forge files.

  3. Proxy

    If you have a proxy connection set up on your system, please try to temporarily disable it to check if it has any effect on the issue. You will need to make sure both "Use setup script" and "Use a proxy server" are disabled.

    Windows 10




    Windows 11




  4. Hosts File

    Follow Microsoft's guide, How to reset the Hosts file back to the default.

  5. Private Relay (macOS)

    If you're using CurseForge on macOS, try to temporarily disable the Private Relay option located under iCloud.

Otherwise, this could be a server issue on our side - you can check the CurseForge Twitter for any related updates, or reach out to us for help.

An unexpected error occurred. Operation failed

Windows

Please make sure that your Windows user has full control over the game's mods folder. For example:


If this doesn't fix the issue, please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Check category or game version filters and try again

This error requires some looking into.

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Failed to delete addon(s)

Please try restarting the app, or repairing the folder permissions, for example:


If neither helps, it's possible that the addon's file is currently locked - make sure that the game (or any other program that could be using the file) isn't running. You can also use software like LockHunter to 'unlock' and delete the file.

Failed to save instance settings

If CurseForge was unable to save the change you made in an instance name, please reach out to us for help.

General install error

Please make sure your network connection is working properly.

Otherwise, this could be a server issue - you can check the CurseForge Twitter for any related updates, or reach out to us for help.

I/O error occurred

This error is related to local mod/addon files, and usually means that CurseForge is enable to interact with them. The reason for that may be one of the following:

  1. The files are locked by the game or by another process, usually a cloud syncing service like OneDrive, iCloud or Dropbox. Try exiting or disabling the service and check if the issue persists.

  2. The files are corrupted. If possible, try manually deleting the specific mod's/addon's folder (outside of the app), and re-installing them.

  3. Temp folder issue - At times, files or folder can get stuck in the system's 'temp' folder, so they can't be moved into the mods/addons directory. Try opening the 'temp' directory (type %temp% in the system's search bar to locate it), then the 'CF' folder, and delete any folders and files inside it.

If you require further help, please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Missing required disk permissions for installation

Minecraft

  • Please make sure that your antivirus software is not blocking any CurseForge or Minecraft files.
  • Make sure that your Windows user has full control over the modding folder. For example:



  • Try running CurseForge as administrator.


Other Games

Please try repairing the folder permissions. For example:


If you're running the app on macOS, please make sure the app and the game have access to the Documents folder in your system:

Oops, that was not supposed to happen!

Please follow these instructions.

Something went wrong, please try again

This error requires some looking into.

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Sorry, we can’t load this project. Missing dependency: []

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

This game is already being tracked by the CurseForge App

The game you are trying to detect is already tracked by the app, and it cannot be added again.

This is an invalid directory or unsupported game

Please make sure to select the folder than contains the game's executable file.

For example, World of Warcraft instances should be added according to the specific installation (Retail/Wrath of the Lich King Classic/Classic). For Retail, the folder _retail_ should be selected.

Minecraft

An access violation occurred when attempting to install Minecraft launcher

Please make sure that your system user has sufficient permissions (read/write) to the modding folder, or try installing the modding folder on a different drive.


Still not working?

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

An invalid folder path was chosen

Please follow these instructions.

An unexpected error occurred while trying to install Minecraft

This error requires some looking into.

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

CMD configuration may be causing issues

Please follow these instructions.

The decryption operation failed, see inner exception

This error is related to network connection and can occur due to a block/conflict between the app and an antivirus (or another program that affects connection, like Intel Killer).


Please close or disable the antivirus/program temporarily, and try to install a mod again.

Failed to create Minecraft directories

Please make sure that your Windows/Mac user has the required permissions to read/write/modify the C:\Users\[your user]\ folder on Windows or the /Users/[your user]/Documents/ on Mac.



If it doesn't help, please select 'Advanced' and select a different location for the modding folder (for example: C:\CurseForge\ or /Users/Shared/CurseForge):

Failed to download the Minecraft launcher due to a network error

Please make sure your network connection is working properly.

Otherwise, this could be a server issue - you can check the CurseForge Twitter for any related updates, or reach out to us for help.

Failed to find Minecraft process

Please try repairing the installation:

Failed to install Minecraft launcher

Please try repairing the installation:


Or installing a modpack with a different modloader type (Forge/Fabric) or version.


Still not working?

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Failed to set installation path

The modding folder directory that you selected is invalid.

The following options cannot be selected:


  1. The desktop or a folder within the desktop
  2. A OneDrive folder, or any folder within the OneDrive directory
  3. The Vanilla Minecraft directory (C:\Users\[user]\AppData\Roaming\.minecraft\)
  4. A path that contains non-English letters
  5. A root folder (C:\, D:\, etc.), as in - the first or top-most directory in the hierarchy
  6. A folder in a hard drive that has low storage space left
  7. A folder that your system user does not have sufficient permissions for (read/write/modify permissions)


If you're not sure which directory to select, we recommend keeping the default path suggested by the app - C:\Users\[user]\curseforge\, or creating a new folder outside of the C:\Users directory, like C:\CurseForge or D:\CurseForge and selecting that.

Failed to unzip Minecraft launcher

This error requires some looking into.

Please reach out to us for help and attach your logs - this will help us determine the cause and get closer to a solution!

Forge Modloader installation failed

Please try the solutions suggested here: Issues Related to the Forge Modloader.

Invalid file

The app's 'Import' option only works with modpacks (not individual mods, or any other type of content) that were exported according to the CurseForge standard.

Java Runtime Environment is missing or out of date

  • Try repairing the installation:

  • Make sure that you have the latest Java version installed.

  • For Forge (modloader) modpacks/custom profiles: try setting your Java installation path in the app according to these steps.

  • Temporarily close or disable any antivirus programs that are running on your system (excluding Windows Defender)

Modloader installation failed

Please try the 'Repair installation' option:

If that doesn't fix the issue, please make sure your network connection is working properly.

Modpack [modpackName] ([modpackId]/[fileId]) was not found

Please reach out to us and send us the full error message (in writing or in a screenshot) and we will fix it!

Profile name should not include special characters

Please select a different name for the profile that doesn't contain special characters like * [ /

Unsupported mod loader

The modloader you're attempting to install in not compatible with the selected Minecraft version.
Please try a different version of the modloader, or a different modloader type.

You need at least 10GB to install new modpacks. Clear some disk space or change folder

Please make sure that you have enough free space on both your system drive (C:) as well as the drive where your modding folder is installed.


The space on your system drive (C:) is required the app uses the local %temp% directory as part of the mod installation process.

World of Warcraft

Failed to create [groupName] sync group. The group name already exists

You already have a sync profile with this name. Please select a different one :)

Other

SMAPI is required to play Stardew Valley with mods

SMAPI is the mod loader for Stardew Valley - it allows mods to run on the game, and is compatible with the game's installation through GOG or through Steam.
For more information on SMAPI, please visit the official website at https://smapi.io/