System.Data.OleDb.OleDbException: Unspecified error

i changed this:

 <asp:DropDownList ID="ddlProducts" runat="server" DataSourceID="AccessDataSourceProducts"
                        DataTextField="ProductName" DataValueField="ProductID" 
                        AppendDataBoundItems="True" Width="302px" TabIndex="9019"  
                      >
                         <asp:ListItem Text="" Value="" />
                    </asp:DropDownList>

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into this:

  If e.Row.RowType = DataControlRowType.DataRow Then
            Dim cmd As New OleDb.OleDbCommand("SELECT DISTINCT * FROM [Products] ORDER BY ProductName ", con)

            Dim ddlProducts As DropDownList = CType(e.Row.FindControl("ddlProducts"), DropDownList)

            Dim da As New OleDbDataAdapter(cmd)

            Dim ds As New DataSet()
            da.Fill(ds)

            ddlProducts.DataTextField = ds.Tables(0).Columns("ProductName").ToString()
            ddlProducts.DataValueField = ds.Tables(0).Columns("ProductID").ToString()

            ddlProducts.DataSource = ds.Tables(0)
            ddlProducts.DataBind()

            ds.Dispose()

        End If

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and now i get this error:
System.Data.OleDb.OleDbException: Unspecified error
GridView1.DataBind()

Do i need to Dispose/Close something else? error is only there when alot of data is pulled from the database. I only have this issue when the website is published on the server. Locally i don't get this error. IIS as webserver