A single user cannot login into admin panel

[urello]

There is one user on cpanel whose admin panel is unavailable neither from WHM nor via direct connection to port 2083.
Also issue occurs only with one theme. If theme is changed for this user then he is able to login.
Cpanel error_log tells nothing.
There is an successful login attempt in access_log

203.170.85.116 - root [05/15/2015:23:37:24 -0000] "POST /xfercpanel HTTP/1.1" 200 0 "https://webcloud85.au.domain.com:2087/cpsess5100439946/scripts4/listaccts?skip=1&search=lin&searchtype=domain_and_user&acctp=30&sortrev=&sortorder=domain" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"
203.170.85.116 - killingk [05/15/2015:23:37:36 -0000] "GET /cpsess5100439946/login/?session=killingk:ra9ukcsOevUwNZg8jPrOtzyiJVXbuIJl1EAUTlFamAc5COk5jsDFbG0sKMyTgm4i,abaed945da973ae4c352ed3acfc29550164c40cf40a43c278882532bf507991e HTTP/1.1" 301 0 "" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"
203.170.85.116 - killingk [05/15/2015:23:37:36 -0000] "GET /cpsess8015009130/frontend/crazycloud/index.html?post_login=10638845069067 HTTP/1.1" 200 0 "" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"
203.170.85.116 - killingk [05/15/2015:23:37:40 -0000] "GET /cpsess8015009130/frontend/crazycloud/main_page_warnings.html HTTP/1.1" 200 0 "https://webcloud85.au.domain.com:2083/cpsess8015009130/frontend/crazycloud/index.html?post_login=10638845069067" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"

There is an unsuccessful login attempt in access_log

203.170.85.116 - root [05/15/2015:23:38:09 -0000] "POST /xfercpanel HTTP/1.1" 200 0 "https://webcloud85.au.domain.com:2087/cpsess5100439946/scripts4/listaccts?skip=1&search=lin&searchtype=domain_and_user&acctp=30&sortrev=&sortorder=domain" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"
203.170.85.116 - linking1 [05/15/2015:23:38:13 -0000] "GET /cpsess5100439946/login/?session=linking1:CYeP10qPlnmtta6VTaG4yqoQSxhYAHH20eE0BoJU88TGWxxW243qkK7klzc9ZoJk,806cda1b112e04b39b3d2fd511038121cf0e8e04d7815afea92f46152eae28db HTTP/1.1" 301 0 "" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"
203.170.85.116 - linking1 [05/15/2015:23:38:13 -0000] "GET /cpsess4296211352/frontend/crazycloud/index.html?post_login=10638845069067 HTTP/1.1" 200 0 "" "Msuccessfulozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:33.0) Gecko/20100101 Firefox/33.0" "-" "-"

As one can note an successful login attempt produces one more http query than unsuccessful one. I think this matters. Could anyone advise how to fix?

 

[Infopro]

Also issue occurs only with one theme.

Assuming this is the style you speak of: crazycloud, there is no such style by that name in the cPanel product. You might want to contact the author of the style for assistance with this.