c1760nw web interface password

Hi there, I've just bought  a c1760nw laser. Setup was easy, everything works.

I wanted to chance the printer name via the web interface. To change anything it wants a password. I did not find a default password in the documentation (why is that so Dell?), so I entered a 4 digit pw myself (at the printer menu). I've tried to use that pw and admin as username but no luck. I thought maybe it's not possible to do changes over the wifi connection and connected the printer via ethernet. No luck.

So what are the credentials to make changes via the web interface?

Thx for any insights, Rado