"Script Extender update failed" (HTTP error 403)

[matcha07642]

I have attempted solutions to common problems

Yes

I have checked that my game version is supported

Yes

OS

Windows 10

Platform

Steam

Description

When launching the game, whether through BG3MM, Steam, Larian Launcher (DX11 or Vulkan), or bg3.exe, I get the error: "Script Extender update failed" (HTTP error 403). I've just started having this problem and I have no idea what is causing it. The issue appeared just randomly without having added any new mods or updating anything. The issue is this error causes the game to crash upon entering cutscenes with NPCs.

I've tried the following potential fixes:

• deleting SE manually (and all related files), reinstalling
• deleting BG3MM, reinstalling (since the above mentioned error is SE failing to update, when BG3MM prompts you to "start the game to complete the installation process", the installation cannot be completed and therefore SE does not work.)
• restarting my PC
• verifying integrity of game files
• reinstalling the game
• deleting all mods (error still occurs)
• loading old saves that previously worked, but now do not

The crash does not produce a CrashDump file. There wasn't a Larian Crash Reporter prompt either. The "gold" log file shows the following:

[16-12-2025 04:42:36:529][D:\Jenkins\workspace\Repo\FW4\Release\Stable\LSProjects\Apps\Gustav\Code\EoCClient\Client\GameStateThreaded.cpp 32 ecl::GameStateThreaded::GameStateWorker::DoWork]: Client Thread start: ClientInit
[16-12-2025 04:42:36:779][D:\Jenkins\workspace\Repo\FW4\Release\Stable\LSProjects\Apps\Gustav\Code\EoCClient\Client\GameStateThreaded.cpp 54 ecl::GameStateThreaded::GameStateWorker::DoWork]: Client Thread ended: ClientInit

I had the SE console enabled before I attempted to manually reinstall it (it doesn't show up now, of course, so I can't take a screenshot) but I didn't see any new errors in the console either. I hope this is a comprehensive enough description of the issue to start. Thank you in advance for any assistance :)

Indications

Diagnostic Files

I've run the batch file but I keep getting an error when trying to upload it here.

Steps to Reproduce

I'm honestly unsure how you could reproduce the issue, but for me it occurs every time I launch the game.

Expected Behavior

Game expected to launch without producing an error and not crash when entering cutscenes in game.

Actual Behavior

Game produces error "Script Extender update failed" (HTTP error 403) and crashes when entering cutscenes in game.

[catboyraiden]

happens to me and my friend too, doesn't even get the error, SE just searches for an update that isn't there.. pretty sure the problem is in the newest patch... I don't even have crash reports, the game just closes.

[matcha07642]

this is gonna sound crazy but it now works again? i didn't do anything else beyond what i stated above, it just worked when i launched the game this afternoon 😭 i guess i should leave this up in case we can figure out what causes this

[WakeXT]

Since it's on the topic of update-error popups, a command to add in ScriptExtenderSettings.json would be great (if there isn't one already I'm not aware of) to suppress the above mentioned error 403 and this one

so they don't show up any longer (if for example BG3's internet access is blocked via firewall rule, so the IGMM doesn't keep redownloading mods).

[catboyraiden]

this is gonna sound crazy but it now works again? i didn't do anything else beyond what i stated above, it just worked when i launched the game this afternoon 😭 i guess i should leave this up in case we can figure out what causes this

you know what, mine's working too now.. but I think the fact that I turned off my firewall completely helped

[matcha07642]

this is gonna sound crazy but it now works again? i didn't do anything else beyond what i stated above, it just worked when i launched the game this afternoon 😭 i guess i should leave this up in case we can figure out what causes this

you know what, mine's working too now.. but I think the fact that I turned off my firewall completely helped

you know, i also turned off my firewall, but that didn't help me so idk

[Norbyte]

Hi,

The updater was catching strays from the Cloudflare bot detection feature, should be all good now.

[Norbyte]

Since it's on the topic of update-error popups, a command to add in ScriptExtenderSettings.json would be great (if there isn't one already I'm not aware of) to suppress the above mentioned error 403 and this one

You can turn the updater off by adding {"DisableUpdates":true} to ScriptExtenderUpdaterConfig.json

[WakeXT]

Since it's on the topic of update-error popups, a command to add in ScriptExtenderSettings.json would be great (if there isn't one already I'm not aware of) to suppress the above mentioned error 403 and this one

You can turn the updater off by adding {"DisableUpdates":true} to ScriptExtenderUpdaterConfig.json

Thanks for the info, imo a suppression-setting would still be convenient to not have to disable/enable both internet access and the updater each time to avoid it throwing a popup-fit ;>.