Summary
We have resolved an issue sending emails from the Customer Record in Sage 50 Accounts.
Description
When clicking the ellipsis button at the end of an email address in the Customer Record:

The button should open the default email program and start composing an email to the selected address, however, it's possible that nothing happens or Sage 50 Accounts closes unexpectedly.
Resolution
NOTE: This issue is resolved in v30.1 and above of Sage 50 Accounts. If you aren't using the latest version, upgrade now.
Another workaround is to copy the email address from the customer record, and manually compose an email in your usual email application.