Hello,
VM Invoice uses the Joomla's core mailer class. So it will use what is in your Joomla Global Configuration.
If you are sending/receiving other Joomla mails (such e.g. registration notification) then I can see no reason why you should not receive VM Invoice emails.
If you have the latest version and you see just "Mail sent" message, then it means Joomla mailing fuction returned no error and that the mail was handed over to mailing server.
You should also check, that you have filled in correct information as regards sender and sender email in VM Invoice. Having incorrect information there (e.g. invalid sender email) may result in mail server refusing the message.
So a few questions:
1. What do you have configured in
Mail Settings in your Joomla Global Configuration?
2. Are other Joomla emails being sent/received?
As regards your questions:
Is there any example page with a running mailconfig?
Not sure what you mean. What kind of example page? (at our demo - demo.tramin.artio.net/joomla15, mail sending is working fine)
And I have seen a mailxxx.php in the adminarea. Should I use this instead?
I do not understand this question. What file / where? How do you want to use it?