Up until recently i was able to send emails through the server with no issues at all. However now i am met with the error message: "SMTP ERROR: Failed to connect to server".

Reading up i can see that this can be caused if port 25 is being blocked, however i am already using port 465. Below are the settings that i am using.

Please help, this is causing me a major headache:
$smtp = new PHPMailer();
$smtp->IsSMTP();
$smtp->SMTPAuth = true;
$smtp->SMTPSecure = "ssl";
$smtp->Host = "localhost";
$smtp->Port = 465;
$smtp->Username = "donotreply@myemailsender.co.uk";
$smtp->Password = "correctemailpassword";
$smtp->SetFrom("donotreply@myemailsender.co.uk", "Friendly Name");
$smtp->AddAddress("receiver@theiremailserver.co.uk");
$smtp->WordWrap = 50;
$smtp->IsHTML(true);
$smtp->Subject = "My chosen subject";
$smtp->Body = "My email body";
$smtp->AltBody = "My email body";
$smtp->Send();

if(!$smtp->send()){
echo "email_failed Error=".$smtp->ErrorInfo;
echo "email_check"."failed"."email_check_end";
}else{
echo "email_sent_to_$to";
echo "email_check"."success"."email_check_end";
}