Page History
...
- It cannot be more than 254 characters long
- It must not contain more than one @
- It must not begin with an @
- It must not begin with a period (.) and there must be at least one period in address
- It cannot have two periods next to each other
- It cannot contain a space
- It must have at least one character between the @ and period in the domain portion
- It must not end with a period
See also
...