>>>I did what you've told me, using another grouping (with expression ncount=30) inside the first one but why it didn't print all, for e.g if I have 4 pages, the 1st page was printed, the second was not, the third printed, and the last was not. Did I miss something ?
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>>My guess is that you aren't resetting the counter variable properly on page breaks. I don't know what you actually did or where you did it.
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>Hi Ed,
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>I gave a check mark on 'start each group on a new page' at the second data grouping which is made the blank page happened, but it's OK now.

You have to reset ncount in the page header, and repeat the preceding subgroup header on each page.