Login to Portal directly

If you have difficulties when signing into the Portal 8, try logging in through this url
localhost:10039/wps/portal/cxml/04_SD9ePMtCP1I800I_KydQvyHFUBADPmuQy?userid=wpsadmin&password=yourpwd

This situation may arise when you try to apply custom theme to default Login page and suddenly the Login Portlet disappears.