Password rejected, no password calls for password and rejects, can I add them somehow

I reset passwords multiple times, but no one can log in as password gets rejected. I tried no password, it asks for one and rejects a blank entry.  I see an add by the web option but can't seem to make it do anything or find instructions in the documentation on how it works. (The documnetation is organized so that finding command prompts on the web interface for the betwork is difficult to impossible by the way).

How is no password supposed to work? Also is rejected passwords a common problem. I am just trying to host an on line game once a month from a mobile hot spot (only internet available to me) so security is not an issue.