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Based on my experience, there are two ways to deal with this situation.
The first method is creating new role group in EA. You can customize the permissions you need for the new group. For details you can refer to part Work with role groups of this article:Exchange Server permissions
The second way is to use the Setup.exe
command with the /PrepareAD
switch to recreate the default security groups. This command will reinitialize the default RBAC roles and groups. Here is the command you can run:
Setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms
More information about prepare AD:Prepare Active Directory and domains for Exchange Server