@Bernhard
Thank you for your post!
When it comes to deleting your Enterprise Apps, you should be able to do this via our Enterprise apps with no way to delete documentation.
Open PowerShell as an administrator.
Run Connect-AzAccount -tenant <TENANT_ID>.
Sign in to Azure AD in the Global Administrator role.
Run Get-AzADServicePrincipal | ForEach-Object { Remove-AzADServicePrincipal -ObjectId $_.Id }.
If you're still having issues deleting your tenant because of the Enterprise Apps, you can try the below steps to hopefully resolve your issue.
Delete tenant - Enterprise Applications:
On your windows desktop search, Open PowerShell ISE as Administrator
Install the needed module, type at promt: Install-Module MSOnline
Then type at prompt: Connect-msolservice
Input a global admin’s credentials for your azure tenant. (eg. User: admin@[organization].onMicrosoft.com + password)
If we have any output please run the following command at the prompt: Get-msolserviceprincipal | remove-msolserviceprincipal (Note you will see a lot of red output on this command, these are applications that cannot be deleted from the tenant, but will not stop you from doing so.)
Log in back to the Azure tenant, and try one more time to delete it.
Additional Link:
Unable to delete tenant if there is enterprise application
Delete a tenant in Azure Active Directory
I hope this helps!
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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