If you cannot send sms message - do not worry, there is another way - send SMS by e-mail. This sending is useful because your recipient will immediately understand exactly who sent this message - in sms text will be inserted your email address. Email address which you want to send sms from email should consist of telephone number (to which you are sending the message) + special symbol @ + special address of mobile operator (usually it consists from subdomain "sms" and website operator address).
For example, a phone number – 0044795XXXXXXX. This is the number English mobile operator "Virgin Mobile" its website - virginmobile.com. So your sender email address must be - 0044795XXXXXXX @sms. virginmobile.com. These rules are applicable for almost all operators in the world.