InfoPath Dev

Hi, I am new to infopath and i recently designed a form (without Sharepoint) and added a digital signature... when one of my colleagues came to sign the form, it stated that 'InfoPath cannot add the signature. Invalid Pointer'. Does anyone know what causes this? Or how to resolve it? Thanks in advance Glenn

Some people can sign it? Just this one user cannot? If so - see what might be different on that user's machine. Maybe they need to install windows / Office updates that others have already installed?