Thank you for posting your query on Microsoft Q&A, from above description I could understand that you are looking for way to use "Global secure access" Private access which has stopped post deleting the application from Enterprise Apps.
Please do correct me if this is not the case by responding in the comments section.
On-boarding to global secure access is a one time process and we don't have a way to reset it. To use Private access with the application, you must have an enterprise application configured. As per Setup overview
Per-App Access is configured by creating a new Global Secure Access app. You create the app, select a connector group, and add network access segments. These settings make up the individual app that you can assign users and groups to.
To configure Per-App Access, you need to have a connector group with at least one active Microsoft Entra ID Application Proxy connector. This connector group handles the traffic to this new application. With Connectors, you can isolate apps per network and connector.
To summarize, the overall process is as follows:
- Create a connector group with at least one active App Proxy connector, if you don't already have one. If you already have a connector group, make sure you're on the latest version.
- Create a Global Secure Access app.
- Assign users and groups to the app.
- Configure Conditional Access policies.
- Enable Microsoft Entra Private Access.
However if you don't want to create a new application and retrieve the old one then you could recover it from Identity > App registration > Deleted Apps > select the App > Click on ... (next to Delete Permanently) > Restore Application
Once application is configured, then do let me know what issues are you facing while trying to do a private access.
Thanks,
Akshay Kaushik
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