Yes, it did the trick. Thank you very much.
I have to make an admission regardless of language which is used in my project ( C# this time ) and after unsuccessful googling the fastest way to receive the answer is to go to this forum.

>>When saved as CSV( I may have several worksheets in xls, and each is saved as csv ) , message box sometimes does appear ( “Save changes ‘yes’ , ‘no’ , ‘cancel’ ) , surely not for all worksheets. IF programmatically save 100 xls files as csv , would it be possible to avoid popping up this message box somehow ?
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>Michael,
>
>Try

oExcel.DisplayAlerts = .F.