The reason for the issue is that transaction log backups can't be performed for databases with SIMPLE recovery model. We generate a message that indicates that a particular database has SIMPLE recovery model.
SQL databases in SIMPLE model are not available for transaction log backup. Do not check that option and the backup would be successful. To perform full sequence of SQL backup please set your base to recovery model FULL.
You can modify the recovery model in Microsoft SQL Server Management Studio: connect to SQL Server, right click on a database, select Properties, Options.
For more information about SQL server recovery models, please see the following article: