There's something wrong with the sign up page. The user attempting to create a new zoho email account is taken to a page where he cannot sign up for an account. Instead of being asked to create a username and password, the user is asked for an already existing email account and password. When this information is entered, it says "enter a valid email address. A mail will be sent to this email to confirm your account and also in case you forgot your password." How does zoho expect to send a confirmation email to an account which does not exist?
When the user enters his existing zoho email information, he is told to "please enter a non-zoho email."
When he enters a non-zoho email and password, he is told "sorry, we are unable to process your request now. Kindly try again."
When you sign up for an email account, you're supposed to be asked for a new username and a new password. Then you get assigned an email account based on that username. This is not what's happening at zoho. Has zoho decided to stop registering new accounts? Because unless somebody there has screwed up, that's the only explanation for sending new users to a page that doesn't let them register.