There is a bug in NetBeans that occurs even when you run project generated by built-in wizard. You got an error (HTTP 404 not foud) suggesting that favicon.ico file is missing, which is obviously not true. The error is annoying because it makes logs messy and consequently makes it difficult to debug other problems.
GET http://localhost:8383/favicon.ico net::ERR_EMPTY_RESPONSE
Move favicon.ico file into img subdirectory (or different one) and add the following line to html head.
<link rel=”shortcut icon” href=”img/favicon.ico”>
Below is an example:
<link rel="shortcut icon" href="img/favicon.ico">