How can I know if my email address has been registered on Alibaba.com or not?

To see whether or not an email address has been registered on Alibaba.com, you can try to create a new account using that email address by clicking here. 

If an error message saying "An account already exists with this email, please select another email address or username” is displayed after you enter the email address into the registration form, it means the email address you are using has been used for account registration either on Alibaba.com or other sub-platforms of Alibaba such as Taobao.com,Alipay.com,1688.com,etc. And you need to change another email which has not been occupied yet to register,or sign in with your account on Taobao.com,Alipay.com,1688.com,etc. directly and confirm activation. 

 If you don’t get an error message, it means that email address has not been used for any account registration.