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It looks like you’ve done a lot of the necessary steps for migrating from AD RMS to Azure Information Protection.
However, there are a few additional things you might want to check:
- Client Configuration: Ensure that all client machines have been properly configured to use Azure Information Protection instead of AD RMS. This includes verifying that the registry settings are correctly pointing to the Azure RMS service.
- Service Discovery: Make sure that the service discovery process is correctly configured. The order for service discovery should be registry, then service connection point (SCP), then cloud.
- Onboarding Controls: Use onboarding controls to manage the transition period where some users might still be using AD RMS while others have moved to Azure Information Protection.
- Content Re-protection: In some cases, you might need to re-protect the content that was previously protected by AD RMS to ensure it can be accessed using Azure Information Protection.
- Permissions and Access: Verify that the permissions and access rights have been correctly migrated and that users have the necessary rights to open the protected files.
Is there a specific error message you’re encountering when trying to open the files? That might provide more clues on what could be going wrong.