ERROR: Cookies are blocked or not supported on new site

I am on hostgator. I created a new multisite following all setup rules.

The MU site is on an addon domain and I have all the wildcards duly set.

I can create sites from the Network admin panel as a super user no problem.

New sign ups however that create sites can’t login using their sent passwords obtaining the cookie error :

[ERROR: Cookies are blocked or not supported by your browser. You must enable cookies to use WordPress.]

I cannot login to the new sites using the superadministrator login or password either.

I am using the multi-domains plugin and it’s working fine as I can create sites under either of the domains added but they seem to work from the Superadministration account only.

On the new sites from wp-signup.php path… If the new users request a password reset they can then log in although they to get an error:

[You attempted to access the “Name Name Name” dashboard, but you do not currently have privileges on this site. If you believe you should be able to access the “Name Name Name” dashboard, please contact your network administrator.

If you reached this screen by accident and meant to visit one of your own sites, here are some shortcuts to help you find your way.

Your Sites

Chris Testing Visit Dashboard | View Site]

Clicking visit dashboard takes me to the login screen again.

I have my domains set as

What am I doing wrong?

Did I miss some code somewhere?