I have the following method that has been working fine until today, I have not changed anything with the code.

Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage(); if(cc != null) { mail.setCcAddresses(cc); } mail.setToAddresses(toAddresses); mail.setReplyTo('******'); mail.setSenderDisplayName('Salesforce Messaging'); mail.setSubject(subject); mail.setHtmlBody(htmlBody); Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });

When I try to deploy I get:
Error: Compile Error: Method does not exist or incorrect signature: void sendEmail(List) from the type Messaging

This started today in both Sandbox and Production.

Does anyone know whats going on?