If I use "Extended Transport Control" to transport requests automatically from DEV system to QA system, where to check the transport logs except tcode SE01/SE09?
I can suggest you a solution to check what was the situation of your request at that time.
This is to do with the Export History of your system.
If you have already verified it then its good or else follow these small steps.
1. As suggested to you in my last post about Transaction STMS, go to it.
2. Click on Import Overview.
3. Select the system your currently working.
4. GoTo History.
5. Click on Export History.
It will provide the history of all the request exports made to the target system by your system at that specified time interval.
If you still can't locate the cause or the problem, you can give feedback.
Good Luck & Regards.