NOTE: I will no go over the actual logic on how to email the invoice as I have already written a post about it, you can find it here http://axwonders.blogspot.com/2011/02/save-microsoft-dynamics-ax-2009-report_23.html
The following is the new control added to the CustTable form under the setup Tab:
Now the logic is very simple. If the a customer account has this checkbox checked then set the Document destination value automatically to Email. Otherwise set the value of the control to Printer. In the picture above we can see that this specific customer has the checkbox checked.
Then the expected result will be to see the Document destination value to Email when a sales order record needs to be invoiced or acknowledged.
Please see the following sequence:
