By what i can see, there could be multiple reasons for it not working:-
1. Wrong Website URL in options->Basic Board Information->Board URL
2. Cache related addons could cause the issue aswell, try disabling them if you have one.
Once disable all your addons and than check if its working or not, make sure to test on inconginto as due to cache, may not work in normal browser. If it works after disabling all addons, than you have to find which addon is causing the issue.
3. It could be related to some issue with your host, once try contacting them if nothing works out.