Crashing - Couldn't add attachment

I’ve purchased a license, but ive been quite disappointed with consistent crashing of the email client. For example, today, i’ve experienced the following and it won’t let me respond to anyone’s email or let is be sent. I’m not trying to add any attachment. It’s just an email with nothing but text inside of its content.

Could you please find out what’s really causing it?

emClient error - crashing