Hi @Azim,
The error "The target principal name is incorrect. Cannot generate SSPI context" can occur when attempting to access Central Admin from the app and web front-end servers. This error can be caused by various reasons, such as misconfigured SPNs, name resolution issues, or insufficient rights for SQL Server service startup accounts. you can try using the Microsoft Kerberos Configuration Manager (KCM) tool to check the causes of the error. Reference: Fix the error with Kerberos Configuration Manager (Recommended).
If it does not resolve the issue, try the solutions in this case: The target principal name is incorrect. Cannot generate SSPI context.
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