To anyone getting error "XML file did not load" please check your K2 plugins. Probably some of them contain incorrect XML markup. Try to disable some until you find which one is causing the issue.

no that not disable your plugin, plugin also work fine.
and still you have any problem then you also have to check costume plugin related K2 .
Its work for me perfectly.
need more help then please explain your problem
thanks
Ajay Gadhavana