Namespace Registry "Link Namespace" fails with missing required code challenge OAuth error

Hi everyone,

I'm trying to link a registered namespace to a Salesforce Dev Hub, but the Link Namespace OAuth flow consistently fails.

I have two Salesforce Developer Edition orgs:

Dev Hub org

•  Org ID: 00DgL00000cC3XJUA0
•  Username: arsalan.46e14c4df64c@agentforce.com
•  My Domain: orgfarm-3d4033bad7-dev-ed.develop.my.salesforce.com

Namespace org

•  Org ID: 00Dak00001B9E06EAF
•  Username: arsalanchauhdary101.51db661d203c@agentforce.com
•  My Domain: orgfarm-7556cdb455-dev-ed.develop.my.salesforce.com
•  Registered namespace: charityfront

The namespace is registered in the second Developer Edition org.

From the Dev Hub, I go to:

Setup → Namespace Registries → Link Namespace

Salesforce opens the OAuth login popup, but instead of displaying the login/authorization screen, the popup immediately returns:

error=invalid_request&error_description=missing%20required%20code%20challenge

Troubleshooting already performed

I have tried the following:

•  Normal browser 
•  Incognito/private browser 
•  Different browser session 
•  Confirmed My Domain is configured 
•  Confirmed both Developer Edition orgs are accessible 
•  Confirmed the SalesforceDX Namespace Registry Connected App exists 
•  Confirmed the Connected App has OAuth enabled 
•  Confirmed the required OAuth scopes are present: 
  •  Access the identity URL service 
  •  Manage user data via APIs 
•  Disabled the org-level Require Proof Key for Code Exchange (PKCE) setting 
•  Verified the relevant OAuth settings are disabled 
•  Installed the latest Salesforce CLI 
•  Salesforce CLI version: 

@salesforce/cli/2.149.9 win32-x64 node-v24.19.0

I also successfully authenticated both orgs through the CLI:

sf org login web --alias CharityFrontDevHub
sf org login web --alias CharityFrontNamespace

Both appear as Connected with sf org list.

The problem therefore appears to occur specifically when Salesforce's Namespace Registry → Link Namespace flow initiates its OAuth authorization.

Additional observation

The SalesforceDX Namespace Registry Connected App appears to be Salesforce-created/managed rather than an application I created for my project.

I also found references to other users experiencing a similar missing required code challenge error during the namespace linking process.

Has anyone encountered this recently with Developer Edition / Dev Hub orgs?

Is there a known Salesforce-side issue with the Namespace Registry OAuth flow, or is there another configuration that needs to be changed to provide the required PKCE code_challenge?

I'm using this for a package namespace, so I need to get the namespace linked to the Dev Hub before I can proceed with packaging.

Any guidance would be greatly appreciated.

#Salesforce Developer  #TrailblazerCommunity