Something is wrong with the website registration. It does not accept any kind of email address. I entered every example but it keeps on saying invalid email.
Please try clearing your cache and refreshing the window. If the email ID is not accepted still, forego the warning and continue with sign up. It should got through. The 'Email ID Invalid' is a bug that came in today after we changed the email server. Sorry for the trouble! It will be fixed in a few hours! Thank you for your patience and support!
Team CrypKart&CrypKoin