Manually you can deselect a radio button using shift+click. In a script you could use Set Field "".
thanks for the reply
But that won't solve my problem. yes you can use shift+click to deselect manually but i want it to deselect the active email and select the inactive one at the end of the day automatically.
You can use a script step "Install OnTimer Script" to call a script that toggles the emails.
So lets assume you have a value list of the email addresses (only 2). Create a script that substitutes the current email address from the value list. After trimming all newline and space characters you are left with the remaining email address.