Username and password on BH ver 1.66

Username - root
Password - <leave blank>

That should work! If not....

menu --> plugins --> red --> system --> scroll down to SetPasswd, install and that will allow you to change it to something memorable!

Have you installed a original BH, or a backup ?

Back-up images have different passwords.
Look for it in the description of the image from the forum that makes it public, or with google search.
After you find it, change it to whatever you want.