So you're still getting the same result after removing basic authentication?
I would check that UseLdapAuth is false or 0 in mp_Sites
I would make sure you have forms authentication configured in Web.config:
<authentication mode="Forms">
<forms name=".mojochangeme" protection="All" timeout="50000000" path="/" cookieless="UseCookies" />
</authentication>
<anonymousIdentification enabled="false" cookieName=".ASPXANONYMOUS" cookieTimeout="43200" cookieSlidingExpiration="true" cookieless="UseCookies" cookieProtection="All" />
If the domain is now different I would check in the mp_Hosts table. For single site installation this may be empty and thats ok. If you see incorrect host names there change to the correct ones.
If the password is long, I would try making it shorter because I remember a bug in an older version where the password parameter in the sql proc was declared shorter than the field length which would cause it to get truncated and login would fail.
Do you know what version of mojoPortal you have? You can look in the mp_SchemaVersion table for mojoportal-core.
Hope it helps,
Joe