Enable logs for RRAS

To help in troubleshooting VPN connection issues, it would be good to have logging enabled on your VPN server. To do so, follow the steps below:

1. To enable RAS logs run “netsh ras set tracing * enabled” from a command prompt.
2. Try to connect.
3. Disable the logs by running “netsh ras set tracing * disabled” from a command prompt.
4. Check the logs at %windir%\tracing directory.

Don't forget to check the Event Viewer --> System logs too.

SQL Server log files

To view log files for SQL Server, the default location is Program Files\Microsoft SQL Server\MSSQL.n\MSSQL\LOG\ERRORLOG and ERRORLOG.n files.