Add the below code to a custom HTML block, update the name in bold to the name of the field.Replace the **** with the word "script"
<**** type="text/javascript">
(document).getElementsByName('FIELDNAME')[0].removeAttribute('checked');
</*****>
Please ensure that you have access to an experienced JavaScript developer.
Marketo Technical Support is not set up to assist with troubleshooting JavaScript.
Here's a sample page: http://info.dbmayberry.com/noinitialbutonvaluechecked.html
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