Thank you all for your inputs what i ended up doing is (and it prob need some ironing out) is inside the Write collection i added 
Dim Format as String 
Dim ColType as Type 
ColType = col.DataType
 If ColType = GetType(String) Then 
Format = "@" 
else 
Format = "0.00" 
End if 
GetWorkbook(handle,Nothing).ActiveSheet.Range(cell,cell).NumberFormat = Format
so i can format cell before writing data, so far it's working fine
Cheers
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Marc Morin
Consultant
PWC
America/New_York
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