Thank you very much Hilmar !

I found that out too just after I've written that maessage ! :-)
I traced another mistake in my form that made trigger not to work correctly. Since I fixed that it works correctly. I recognized that triggers fire the buffered tables in moment I apply changes using TableUpdate(). This is because of my poor English :-) I just didn't understand the help topic correctly for the first time. Sorry for disturbing and thank you one more time for finding time to read my message and answer me !

Best regards.
Eugene