Regarding CUBECART built-in mail function. This has been an issue for YEARS...
I found the solution to the issue and appearantly it is only with myhosting.com servers. So if someone has an account with myhosting, they will NOT be able to use their mail() function or smtp function to send mail through myhosting.com's servers. I will attach the smtp file (fix) I am using with one line of minor modification for anyone else who may run into this problem who is using myhosting.com services. This is a fix for v3 and v4.
Basically, you can only use mail option SMTP with myhosting.com with this edited version of the SMTP file included. The basic installation smtp file will NOT WORK- It must be modified for the automatic mail function to work. You must use smtp mail setting under general settings, select "yes" user requires authentication and put in the credentials for email@example.com
I had a lot of trouble with this and previous versions... I hope this can help other people who run into a similar situation.
Solution Replace the file under WebRoot\classes\smpt.php for Version 3
Webroot\classes\htmlMimeMail\smtp.php Version 4