Recently I found myself installing a CRM 2016 server on a development box to begin the process of fixing issues to migrate to D365 on-prem. This is one of the issues that I encountered. The error read as follows:
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Microsoft Dynamics CRM Setup
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Action Microsoft.Crm.Setup.Server.GrantConfigDBDatabaseAccessAction failed.
Windows NT user or group 'DOMAIN\SQLAccessGroup {Guid}' not found. Check the name again.
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Retry Cancel
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Resolution:
This issue generally occurs when you have open sessions for the target SQL server using the same login credentials as that are being used by the installer. In my case, I had a SQL Management Studio session opened. Once I closed this and hit Retry on the Front End server to continue with the installation, the issue was resolved.