Hello,
A part of the setup of CRM Connection is performed by the integration user (after the solution is imported and roles assigned, the integration user is used in the part of the setup that assigns roles to the corresponding team).
In your case, this fails because you may have temporarily removed the System Administrator role from the integration user.
To get out of this we may have to enable your CRM Connection Setup from the back-end, because if you got this far in the setup, the integration solution is already imported. This can be done via a support ticket your partner or CSP can raise on your behalf.
However, you still need to do a few things.
1. Sign in to the Dynamics 365 Sales Environment with the admin account, and open Advanced Settings\Security\Teams
2. The view may be filtered to "Local Business Owner Teams". Change that view to show "All Owner Teams"
3. Find and select the team whose name contains the name of your Business Central company. It should have a name that starts with "BCI - <name of your Business Central company>". You have integrated to this environment from CRONUS xxx, so this team name should contain the name of that company. This is the default owning team for the business unit that represents your Business Central company in CDS.
4. For this team, choose "Manage Roles"
5. This team already has one security role. Do not remove this role, just add the following two security roles to this team: "Dynamics 365 Business Central Integration Administrator" and "Dynamics 365 Business Central Integration User".
6. For user john@contoso.com, re-assign the System Administrator role (this is the workaround for the authentication error that you are getting).
Now that you have assigned the security roles to the corresponding team, and reapplied the workaround on the integration user, and we may have to enabled your CRM Connection Setup from the back-end, your integration to Dynamics 365 Sales should start working.
Best is therefore to raise a support ticket via your partner / csp or via yourself if you are entitled to do so, so we can assist you further. These are however the steps that must be done afterwards.
Thanks.
