In Grasshopper when using pandas in a Python3 component, I get an error “1. Error executing script: unknown locale: en-US [7:1]” and have confirmed same behaviour from clients. The fix: 1: Open Rhino 2: Run ‘ScriptEditor’ command 3: Make new Python Script. 4: Run this code: import locale loca…

I was able to resolve this with: rhino_startup.py import locale try: locale.setlocale(locale.LC_ALL, ‘’) except: pass try: current = locale.setlocale(locale.LC_ALL, None) if '-' in current: locale.setlocale( locale.LC_ALL, current.replace('-', '_') ) except: pass

I believe i’m running into the same issue on my client’s PC after update. I was getting this error in the GH python component: 1. Error running script: partially initialized module ‘pandas’ has no attribute ‘_pandas_datetime_CAPI’ (most likely due to a circular import) [3:1] After re-installing p…

This is the snippet and possible solution i found but i see you already have it in your code [image] Rhino 8 Feature: ScriptEditor (CPython, CSharp) Serengeti (Rhino WIP) @enmerk4r @Wilfried What happens if you set the locale manually before importing pandas …

@eirannejad Could you have a look at this please?

Updated from 8.31 to 8.32 but the problem persists

@Calcman This is a known issue with pandas on Windows. The underlying problem is that Windows locale names are not very standard and python locale module sometimes fails at processing them. Run this script and tell me what it prints: import locale print(locale.getlocale()) This is what it prints …

Hi Ehsan, thank you for your help. I’m getting the following from the script environment: Traceback (most recent call last): File “file:///C:/Users/Asus/.rhinocode/stage/5uq5u5yf.c5y”, line 2, in NameError: name ‘locale’ is not defined The other snippet you shared was already part of my script. …

Ya I had a script like this by default to fix Windows-style locale names but that ended up messing up other locale based stuff. I am glad this works for you. Thanks for the update.

Hi Ehsan, how can we get a permanent fix for this. It means pandas is not robust to include in any tools in Rhino?

I needed to reset Python Runtime in Rhino for this to work. Very fragile fix

Let me take another look and see if I can come up with a solution. RH-81130 ScriptEditor: Python 3 to set locale before running script

Error in Rhino 8 SR31 when using pandas: unknown locale: en-US [7:1]

Grasshopper

Calcman May 20, 2026, 7:33am 4

This is the snippet and possible solution i found but i see you already have it in your code

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Error in Rhino 8 SR31 when using pandas: unknown locale: en-US [7:1]

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