Fix Blueimp error

Hello, I have a bug in the code that I havent been able to find and fix. The code is in PHP and Java Script. In Local Host there is no error (it work perfectly) ... It only appears when I upload the script to the server in my Hosting service (with cPanel). The code is a form that allows to fill in the blanks data about properties with images. The specific problem is with the image uploader of the form. Whats happening? When I upload images it shows the following error: "SyntaxError: Unexpected token < in JSON at position 0", but when I "refresh" after the uploading process the webpage shows the images fine.... besides this when I delete the images that have been uploaded, it seems like dont work fine, but after refreshing I can see the images have been removed properly. I shouldnt use the Refresh button for this... because it should shown by ajax without refreshing. Besides when I delete the images that have been uploaded, it seems like dont work fine, but after refreshing I can see the images have been removed properly. I shouldnt use the Refresh button for this. Notice: The tool Im using to manage the image uploads is JQuery Blueimp.