Make sure the login page  has anonymous access to serve.
I tested the login page and it can be accessed without authentication:
can be opened by anyone.
Try 1 & 2 if does not work please file a daycare for further assistance.
1. In "Day CQ Login Selector Authentication Handler" for path info add an empty row then verify.
2. Delete the existing entry for "Day CQ Login Selector Authentication Handler" , Configure your custom at repository level & verify
thanks, 1) was the problem. It works if I either remove the Path Info or if I specify the resource with the .html extension.