Try the following: For iRow = 0 To dgvPreview.RowCount - 1 For iCols = 0 To dgvPreview.ColumnCount - 1 (Note the additional "- 1" at the end of the lines) Maybe it is also helpful for your further devolpments to use try-catch-blocks, to handle exceptions. Normally the Exception itself contains several useful information, which could help you to identify the error's position and circumstances.

So, you looked at one example that used ODP.NET. There are others in that list that use other database providers that work with Oracle. Filippo1974 wrote: Is it possible to manage this kind of field without install this? Keep reading through the results list and find out. This is what is called "research", and it's an integral part of any programming job. A guide to posting questions on CodeProject[^] Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic      2006, 2007, 2008

Yes! It works exactly as I need. Thank you wery much for you suggestion! Filippo