If you ever get this error, whether it is in a SharePoint app or ASP.Net app, or directly in SQL Server, never delete the files directly. This will most likely cripple your application. Instead, truncate the database transaction logs directly from SQL Server Management Studio.

Right-click on the database in which you want to remove the transaction logs. Choose ‘Transaction Log’ as ‘Backup Type’. then, in the ‘Options’ section, you will see that there is a radio button to ‘Truncate Log’. Make sure that it’s selected. Click OK, and you’re done.