alow only alphanumric in column and validate on click on Save button

Hi ,

Need to validate column to allow only alphanumeric characters and no special characters . Need to show message if it has invalid characters before saving , click of built in excel Save button.
How to do this using macro.I am new to excel vba/macro

Thanks,
Basawaraj

Maybe you can go with Data validation on that allow make only what u want...