No given Value for one or more required parameters

Nov 15 2017 6:21 PM

I have a database Oledb. With several textbox and comboboxs. One combobox I have added numbers to selecte from 1,2,3 the Winform works fine but if i change the options to A,B,C I get No value given for one or more required parameter.The oledb / Access file is set to Short text.

Any idea why this happens?