Came across the site emailisvalid.com. Wondered if anyone else had used it and whether or not it worked.
I have never used it but by reading other comment I can see that it's not a reliable option for email. In any case you should never use it for confidential or valuable correspondences.
I tried it, it works sometime and sometime it won't.
I haven't tried it but can say that you can give it a try.It creates a disposable email address which is not secure as regular email service providers like Gmail,Outlook etc..Hence,you must avoid storing or using personal data in it.