C# Call to working Exe program thats updates MS SQL. Accessproblem

I have a small exe program using log4net dll. ([login to view URL]) The program is working with commandline. Inside ther program the log shows the actual user. Works fine in commandline (cmd /C) inside a C# program I try to call the same exe... var processStartInfo = new ProcessStartInfo { CreateNoWindow = true, UseShellExecute = false, FileName = "[login to view URL]", Arguments ="/C [login to view URL] -f testfile", RedirectStandardError = true, RedirectStandardOutput = true, }; By doing this the process user changes. = shows in log. (Natural behavior because the program is run with another user) The Database does not receive the new record. The connection string for log4net is <connectionString value="Data Source=JOHLIN\SQLEXPRESS;Initial Catalog=Log4NetDb;Trusted_Connection=Yes;" /> Its not the normal login connection with a user and password. The connection is with trusted user login. Need to know how to find the user that tries to connect to the database and how to add a user for this. - Add the user needed to create a record. - Add a user that can read-only This is a perfect TeamViewer project. My estimation is 1-2 hours