Microsoft 365 Windows 11 external user or guest user sign in

Take this:

Step 1: Enable Guest Access in Entra ID
Add CompanyA User as a Guest: In CompanyB's Entra ID, add the employee from CompanyA as a guest user. This can be done through the Entra ID portal by navigating to Users > New guest user and entering the employee's email address.

Assign Appropriate Roles: Ensure the guest user has the necessary roles and permissions to access the required resources.

Step 2: Configure Intune Policies
Create a Device Configuration Profile: In Intune, create a device configuration profile that allows guest users to sign in. Navigate to Devices > Configuration profiles > Create profile and select the appropriate settings.

Assign the Profile to Devices: Assign the configuration profile to the Windows 11 Pro computers that the guest user will be using.

Step 3: Set Up Windows 11 Pro Computer
Enable Other User Login: Ensure that the Windows 11 Pro computer is set up to allow login from other users. This can be done by enabling the "Other user" option on the login screen. You can follow the steps outlined here to enable this option.

Sign In with Guest Account: The employee from CompanyA can now sign in using their guest account credentials. They should see the "Other user" option on the login screen, where they can enter their Entra ID credentials.

Step 4: Verify Access and Permissions
Test Access: Have the employee from CompanyA sign in to the Windows 11 Pro computer and verify that they can access the necessary resources and applications.

Adjust Permissions if Needed: If the employee encounters any access issues, review and adjust the permissions in Entra ID and Intune as needed.