The provided account MSI@50342 does not have access to subscription ID

I got mine to work. Here are the steps I took. Got me through the verification. Now it is deploying. Hope this helps you.

#Uninstall all Az modules
Get-Module -ListAvailable | where {$_.Name -like "Az.*"} | Uninstall-Module -Force
# Then I went back in the release notes and found wich release of the Az modules had Az.Accounts 4.0.2 and installed this
Install-Module -Name Az -RequiredVersion 13.2.0
# Uninstalled Az.Resources 7.8.1
Uninstall-Module az.resources -RequiredVersion 7.8.1
# Then made sure these versions of the modules were installed
install-module Az.Resources -RequiredVersion 7.8.0
install-module Az.Accounts -RequiredVersion 4.0.2
Install-Module az.storage -RequiredVersion 8.1.0 

I have worked on this issue on a stack and have worked together with Microsoft to fix the issue. We encountered multiple issues, so I have collected all the issues we came across and written about it.

I have published all the different steps we took to resolve it on my webpage:
https://www.chkja.dk/2025/10/27/azure-local-exception-caught-in-test-azstackhciarcintegration-validator/

Hi Guillaume MANCERON,

The error message indicates that the account MSI@50342 does not have the necessary permissions to access the specified subscription. While some guidance suggests downgrading the Az.Accounts module to version 4.0.2, in your case this caused earlier failures, so let’s verify both the module consistency and account permissions.

Note: Ensure that only the correct module versions are installed on all nodes. Having multiple or mismatched versions of the Az modules may cause authentication or subscription access issues (Az.Resources 7.8.0 and Az.Accounts 4.0.2)

Verify the version of Az.accounts PS module installed on the nodes of the cluster.

Get-InstalledModule az.accounts -Allversions

If any other version apart from 4.0.2 is installed on the nodes follow the below steps:

Uninstall all the versions of az.accounts on the nodes

uninstall-Module az.accounts  -allversions

Install version 4.0.2 on the nodes.

install-Module az.accounts -RequiredVersion 4.0.2

Then, verify with below command

Get-InstalledModule -Name Az.Accounts -AllVersions

To resolve the issue, please ensure the correct account and permissions are in place by following these steps:

1. Verify Subscription and Account:
   • Log in to the Azure Portal with the account you're using for the deployment.
   • Confirm that you are in the correct tenant and subscription. If you have multiple subscriptions, make sure the one you've specified for the deployment is the active one.
2. Assign Required RBAC Roles:
   • Navigate to the subscription in the Azure Portal.
   • Go to Access control (IAM).
   • Click + Add to add a role assignment.
   • Assign the Contributor or Owner role to the account or service principal used for the deployment. The Owner role provides full control and is often necessary for registration. If you're using a service principal (the MSI), make sure to select it as the member.

After these steps, retry the Azure Stack HCI deployment and the validation process.

Please find related official documentations for reference:

https://learn.microsoft.com/en-us/azure/azure-local/deploy/deployment-arc-register-server-permissions?view=azloc-2508

https://learn.microsoft.com/en-us/azure/azure-local/manage/assign-vm-rbac-roles?view=azloc-2508

Once Arc integration is completed and the account has proper permissions, you should be able to proceed with the deployment successfully.

Hope this helps! Please let me know if you have any further queries.