You just registered on hi5 using your e-mail address and you can't find the e-mail from hi5 which contains your activation code?
This small tip will help you to know where to get your activation code for hi5 after registration.
Yahoo mail accounts
If you have used your yahoo e-mail address to register hi5, you will have to check the Spam folder in your yahoo mail inbox. Open the Spam folder to get the activation message from hi5.
Hotmail/Windows Live mail accounts
For Hotmail or Live e-mail addresses used for hi5 registrations, check your Junk folder in your mail inbox.