Login comes back to login page with empty fields - no error, but doesn't log me in

The most common cause is when you have deployed your server on http instead of https, and the secure.cookie.boolean.param has not been set to false in node.properties.  To solve the problem, set secure.cookie.boolean.param=false in node.properties, re-install and re-start.  

The reason this occurs is: we have a security setting which by default does not allow session cookies to be transmitted over https.  (It is inherently insecure to do so, because a man-in-the-middle can steal your session id and use it to impersonate you.)  If you have to run on http instead of https, you have to disable this security setting as per the notes above.

Sometimes going to https://localhost/oms instead of https://localhost/ will solve this issue.