RE: Differenz between "Dynamics 365 custom“ and "Sales Professional" App
Hi Mequan,
thanks for your help. Here our environment. We hope you have a hint for us, how we can solve that problem.
1) Our Dynamics apps
You see the Dynamics 365 custom and the sales professional app.

2) Environments
We have two environments. One is the standard environment. The Dynamics 365 custom related obviously to that. The other one is the production environment which is obviously used by the Sales Professional App (for what ever reason).

3) Setting of the Production environment
If we mark the production environment, we get the settings button and can set the behavior to „only Unified Inteface"


4) Settings of the default environment
If we mark the default environment, we do not get a setting button.

5) Dynamics 365 custom app
If we open the Dynamics 365 custom app, we get the message: "This is an older app and may have features or customizations that are not supported in the Unified Interface. For best results, create a model-based app for the Unified Interface."
If we open the Sales Professional app, we get no error message and have a Unified Interface.

Do you have an idea?
Thanks for your help Phadrus