Hi, I did a test again last night without changing anything in my code but just removed the 400 records I have finished before it hanged. Then it has not hanged and ran for 8 hours, finished 1500 records. I have checked the data around the 400th record but it seems the data is just a normal one. Anyway, I will do some more test to check if the hanging problem is reproductive or just by accident. Thanks.

Power

>Maybe TableB grow very much due to writing all modem's communication to it?