Thanks for the reply.

It's maintenance screen for updating a confirmation type character field. The field holds 1 of 4 values, P for phone, M for Machine, E for Email, or N for No confirmation. The grid holds a list of records and sets a filter to confirmation method = 'E' for Email. With this particular screen I want the user to click the check box for the corresponding record in the grid and in the valid event of the check box I wanted to change the E to a M in the table.