I know the answer might be found in this site. But this problem still exist after I upgraded to v2.3, so I would like to explain my situation and ask again.The situation is:I upgraded both my K2 site into K2 v2.3, thenSite A, which is still Joomla 1.5.15 (at hosting service A)  lightbox works perfect,Site B, which is Joomla 1.5.18 (at hosting service B)  lightbox didn't work well such as  **nothing happened when I click cancel or save button, which means the button didn't work  **extra field didn't change to related fields what it should be when I changed the categoryI tried to disable all other jQuery, mootool moudules at the same page, but the problem still not being solved.I don't understand what's the problem. Why lightbox can work perfectly in a site, but not well in another?  The only difference I can tell here is hosting space. But does this influence the performance of K2?So, anybody can help me to solve this problem at site B?