This thread is old, but I found the solution. I upgraded to version 2.5.5 i is resolved. To update, simply download the latest version of K2 and install the extensions manager. (preserves the posts but delete the css).

I hope it helps someone!

Jordi thank you very, you have made my day! Whoohoo No excuse now for not updating... a world of work...drat, blessings are always mixed.

i have same issue i m waiting some one reponse aswell

SAME ISSUE HERE!

Invalid backend response.
Data is not JSON.

The latest K2 version 2.5.7.

Is this been solved? Please, any advice?

Hello

Invalid backend response.
Data is not JSON.

The latest K2 version 2.5.7.

Is this been solved? Please, any advice?


Help, Help.

:angry:
SAME PROBLEM

there is no answer? :blink:


1. seeing Blank page after upload image
and
2. seeing same error "Invalid backend response. Data is not JSON." when need to load image frome "browse server"

Hi. To anyone facing this issue:

The K2 media manager is working with JSON requests. So if anything other than JSON comes into the server response it will break it. Usually this happens for two reasons. The first one is that there is en error on the page. To handle this you can try setting error reporting to "None" under Joomla! configuration. If that doesn't solve ypur issue, then probably there is some other extension that it's spitting some output breaking the JSON. These extensions that are being executed on every page are System Plugins. So trying to disable some of them may also solve the issue. An example of an extension that is breaking the requests by spitting HTML code in EVERY page is the JomSocial.

imagine! i post 17 items with K2 and its image upload and its works good, but few days later without any change in my setting i wanna to send a new item and i watch this **** blank screen. :blink: :pinch:

plz helpppppppp :(

@mehrdad

A blank screen indicates a PHP error. Enable the error reporting under Joomla! configuration to see what's the error.