Ah.. so you are using GoDaddy.
Ok, it seems you are using Windows hosting plan.
In this case, you need to open your File Manager from GoDaddy control panel and then go to your "machform/data" folder.
Set all the permission of this folder to "Writable" using the File Manager.
Then try to test with a new form.
Regarding the email, you need to configure your config.php file to use GoDaddy SMTP server.
Based on their article here:
http://help.godaddy.com/article/951
Modify your config.php and set these lines:
define('USE_SMTP',true);
define('SMTP_HOST','relay-hosting.secureserver.net');
define('SMTP_PORT',25);
you can left the other as default.
If the problem persist and you need direct help, please contact us directly: customer.service [at] appnitro.com
Many of MachForm users are using GoDaddy.
MachForm Founder