Guest Invite New-AzureADMSInvitation error "Object reference not set to an instance of an object"

Question

I'm following the https://learn.microsoft.com/en-us/azure/active-directory/external-identities/b2b-quickstart-invite-powershell article, but getting an "Object reference not set to an instance of an object" error when running the New-AzureADMSInvitation command.

I'm running this from a on-prem vm. The goal is to auto-invite B2B users that are added to an application we have on-prem.

I have a registered app that I'm using to connect and have granted admin consent for the following MSGraph API permissions: User.Invite.All, User.ManageIdentities.All, User.ReadWrite.All

I load all the variables for the registered app, tenant, etc. , then this...

Import-Module -Name AzureADPreview -force

# Get Access Token

$azurePassword = ConvertTo-SecureString $ClientSecret -AsPlainText -Force

$psCred = New-Object System.Management.Automation.PSCredential($AplicationId , $azurePassword)

Connect-AzAccount -Credential $psCred -TenantId $TenantId -ServicePrincipal

$context = [Microsoft.Azure.Commands.Common.Authentication.Abstractions.AzureRmProfileProvider]::Instance.Profile.DefaultContext

$aadToken = [Microsoft.Azure.Commands.Common.Authentication.AzureSession]::Instance.AuthenticationFactory.Authenticate($context.Account, $context.Environment, $context.Tenant.Id.ToString(), $null, [Microsoft.Azure.Commands.Common.Authentication.ShowDialog]::Never, $null, "https://graph.windows.net").AccessToken

Connect-AzureAD -AadAccessToken $aadToken -AccountId $context.Account.Id -TenantId $context.tenant.id

After running the above it displays

If I run Get-AzureADUser -All $true it shows all the users in my tenant correctly and it will let me add/delete regular users.

But if I try to run the following i get New-AzureADMSInvitation : Object reference not set to an instance of an object.

New-AzureADMSInvitation -InvitedUserEmailAddress $email.'InvitedUserEmailAddress' -InvitedUserDisplayName $email.Name -InviteRedirectUrl https://myapps.microsoft.com -SendInvitationMessage:$true

Answer 1

Hi @Michael Spencer

Azure AD PowerShell is about to be deprecated, you can use the latest graph PowerShell to invite B2B collaboration users to your tenant.

Import-Module Microsoft.Graph.Identity.SignIns

Connect-MgGraph -Scopes "User.Invite.All"

$params = @{
	InvitedUserEmailAddress = "admin@fabrikam.com"
	InviteRedirectUrl = "https://myapp.contoso.com"
}

New-MgInvitation -BodyParameter $params

Hope this helps.

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Answer 2

Hi @Michael Spencer

This is because you are using Azure AD graph access token to connect to Microsoft graph powershell, and New-MgInvitation cmdlet is a Microsoft graph powershell command, which does not support Azure AD graph access token, that's what is causing the issue.

If you must use an Azure AD graph access token, then you should use that token to connect to Azure AD and then use Azure AD powershell commands to invite external users to collaborate.

Connect to Azure AD:

Connect-AzureAD -AadAccessToken $aadToken -AccountId $context.Account.Id -TenantId $context.tenant.id

Invite users:

New-AzureADMSInvitation -InvitedUserEmailAddress someexternaluser@externaldomain.com -SendInvitationMessage $True -InviteRedirectUrl "http://myapps.microsoft.com"

Hope this helps.

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Answer 3

I need to be able to script this, so far I have this, which works as far as authentication apparently.

$azurePassword = ConvertTo-SecureString $ClientSecret -AsPlainText -Force

$psCred = New-Object System.Management.Automation.PSCredential($AplicationId , $azurePassword)

Connect-AzAccount -Credential $psCred -TenantId $TenantId -ServicePrincipal

$context = [Microsoft.Azure.Commands.Common.Authentication.Abstractions.AzureRmProfileProvider]::Instance.Profile.DefaultContext

$aadToken = [Microsoft.Azure.Commands.Common.Authentication.AzureSession]::Instance.AuthenticationFactory.Authenticate($context.Account, $context.Environment, $context.Tenant.Id.ToString(), $null, [Microsoft.Azure.Commands.Common.Authentication.ShowDialog]::Never, $null, "https://graph.windows.net").AccessToken

Connect-AzureAD -AadAccessToken $aadToken -AccountId $context.Account.Id -TenantId $context.tenant.id

Connect-MgGraph -AccessToken $aadToken

And I get the "Welcome To Microsoft Graph!" response.
When I then try:

 $params = @{
	    InvitedUserEmailAddress = $email.'InvitedUserEmailAddress'
	    InviteRedirectUrl = "https://myapp.microsoft.com"
    }

    New-MgInvitation -BodyParameter $params

It errors with:

New-MgInvitation : Access token validation failure. Invalid audience.

But I can list, add, delete regular users w/o issue.

Answer 4

Got there, eventually.

Thanks

Answer 5

Success !
Several issues: Cert must be installed in user's store, won't be found if it's in the local machine store !
Missing modules and 2 versions of Microsoft.Graph.Authentication, so it wouldn't load correctly.

# load configs
. Import-Module "$($PWD)\UserUpdate_config.ps1" -force

# enforce TLS1.2
[Net.ServicePointManager]::SecurityProtocol  = [Net.SecurityProtocolType]::Tls12

Import-Module Microsoft.Graph.Identity.SignIns -force
Import-Module Microsoft.Graph.Authentication -force
Import-Module Microsoft.Graph.Users -force
Import-Module Microsoft.Graph.Groups -force

# cert must be in user's store to be seen
Connect-MgGraph -ClientID $AplicationId -TenantId $TenantId -CertificateThumbprint $certthumb -ContextScope Process

# get group object used by app
$relgroupinfo = New-MgDirectoryObject -Id $(Get-MgGroup -Filter "DisplayName eq '$($relgroup)'").Id

# get users to add. This will eventually be pulled directly from the app via SQL
$invitations = import-csv -Path $invitespath

foreach ($usit in $invitations) {
    # create user and send invite
    $userinfo = New-MgInvitation -InvitedUserDisplayName $usit.'Name' -InvitedUserEmailAddress $usit.'InvitedUserEmailAddress' -InviteRedirectUrl "https://myapp.microsoft.com" -SendInvitationMessage
    # add user to group
    New-MgGroupMember -GroupId $group2add.Id -DirectoryObjectId $userinfo.Id
}

Disconnect-MgGraph