MDaemon(all versions) uses <MDaemon>\logs folder for log files storage(where <MDaemon> is server installation folder, C:\MDaemon by default). You should enter <MDaemon>\logs path in MailDetective settings (Program settings -> Mail Server -> Path to log files).
All is same as in version 7.x, but you need to switch on one more option: Create 'All' log
1. Select Setup -> Logging options...
2. On the Log Mode tab switch on Create a new set of log files each day option
3. On the Maintenance tab switch off all options and set Maximum log file size value to zero
4. On the Options tab switch on the following options: Log message parsing activities, Log AntiVirus activity and Log Spam Filter activity:
1. Select Setup -> Logging options...
2. Switch on the following options: Create a new set of log files each day and Log SMTP activity
3. Set Maximum log file size value to zero.