Thanks It opened when I put run again I have another problem I'm using two linked lists and I opened two files for each one but when I write list to file It writes both lists in the two files .
here is the code
void save (school *c,school *m)
printf("\nFile one has been saved");
printf("\nFile two has been saved");
Dim Adapter As New OleDbDataAdapter
Dim Command As New OleDbCommand
Dim xFrom As String = dtpFrom.Value.ToString.Substring(0, dtpFrom.Value.ToString.IndexOf(" "))
Dim xTo As String = dtpTo.Value.ToString.Substring(0, dtpTo.Value.ToString.IndexOf(" "))
sqlQuery = MainQuery ...