Nprinting server installation problem

[Qiyanlu66]

When I installed the nprinting server followed the video successful, and going to localhost:4993, I can not log in with the admin email and password that I just created.

I am pretty sure I entered the correct email and password I juse create because I uninstalled Nprinting server several times  to make sure I have entered the correct email and password 

Can someone please help me with this?

[Qiyanlu66]

When I checked the nprinting webengine log, I found the following lines repeating a lot:
!!!!!!!!!!!!!!!! LICENSE VIOLATIONS DETECTED
The number of USERS exeeds the current license limit (1 found, but 0 allowed).

Is this normal log when you first login?