Hi. First time using Umbraco. The development of the site went well, but the moment I tried to publish it on the live server I got some weird problem. 

I copied absolutely everything there was on the first server to the live (second) one, and the site works good. But when I go /umbraco, nothing loads and I get a Error: No module: umbraco.security in the console. 

The umbraco.security file's there. 

Any idea what could be the problem? 

Thanks