That certainly did the trick, or, or atleast your attention did. It seems like the admpasswd.sh isn't really stable, because it didn't gave me any errormsges when I used it. However, I changed the password with the help of htpasswd, (which I figured generated the same types of passwords), and then it worked.
1. htpasswd -n admin
2. <inputs password twice>
3. Copy the result to the "lsws/admin/conf/htpasswd"-file.
Thanks alot mistwang!