Hi there,
It's vital that your clients have the option to save their XML files for T4's. Don't worry, I'd be glad to steer you in the right direction.
In order for your clients to be able to do this, they'll need to set up their transmitter number through the Payroll settings. If your clients don't have a transmitter number, they can enter 555555 as a default number. After setting this up, they should be able to view and save the T4 XML file. Here's a handy article which includes additional information about this: How to prepare T4 slips and summary
In case you have other questions, feel free to contact our support team using this link here.
