Error - 'TCP provider: A connection attempt failed because the connected party did not properly respond...'

This is a local environment issue. The SFDC client PC's are likely trying to connect to a SQL Server Instance on a virtual machine using an alias.
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The server and SQL Server Instance names are probably correct, but the port number may be incorrect on the alias.
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Make sure that the port number of the SQL Server Instance that you are trying to connect to is correct. For port number settings, you can use SQL Server Configuration Manager.
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Fixing the port number on the alias should resolve the issue.
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Also, launch the firewall exceptions list and whitelist the following file paths and release the port number:-