I'm not sure why you cannot login to domain1 with the default user/password.
Can you create another domain and try it again?
To create domain:
<install-dir>/bin/asadmin create-domain --adminport <port-number> <domain-name>
you'll be prompted with the user and password.
<install-dir>/bin/asadmin start-domain <domain-name>
Now, try logging in via admin-console:
http:<host-name>:<port-number>
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