Hi Steve and thanks for your help.
I ve closed the connexion because i've found someone who had the same problem with vb and he said there was a bug with the OLEDB and it has to close and open again to make it works.
But in both case it doesn't work, if i close or not the issue is the same, and even if i dont do the isnert, only the create table, all my columns will be on data type Standard instead of the data type i define.
I really don't understand what's happening, if i run the create table with an incorrect datatype like this :
Create table Feuil1(No_id testdatadatatype, valeur decimal(18,2)No_id int, valeur decimal(18,2))
the request will fail so it means it has to receive a good datatype to work, but whatever correct datatype i ask, it will become Standard in Excel file.