Log4Net AdoNetAppender using SQL Server Express DB instead of LocalDB
Problem After turning on Log4Net debugging by adding the followings to the windows service project App.config file: <appSettings> <add key="log4net.Internal.Debug" value="true"/> </appSettings> <system.diagnostics> <trace autoflush="true"> <listeners> <add name="textWriterTraceListener" type="System.Diagnostics.TextWriterTraceListener" initializeData="C:\Temp\log4net.log" /> </listeners> </trace> </system.diagnostics> Configuring Log4Net AdoNetAppender with LocalDB has not worked due to the following error: System.Data.SqlClient.SqlException (0x80131904): Cannot open database "Log4NetDB" requested by the login. The login failed. Login failed for user 'NT AUTHORITY\SYSTEM'. Solution Instead of using LocalDb, use SQL Server 2017 Express as follows: 1.