I'm using a site in Joomla 2.5.27 and a template with K2 2.6.8.
I attach the K2 informations.
I have a serious problem: I can not load images to an item!
I enter an item, go to "Image", I click on "browse" or "browse server", I select the image and .... nothing happens, not even waiting for "hours" and uploading tiny pictures !!!
No errors of javascript or joomla appear, it does nothing!
If I select "save" or "save& close", having uploaded a picture of the tiny weight, after 1-2 minutes joomla close the tab of the item and then I find that the image has been loaded.
If I try to load a picture a bit 'bigger, nothing to do, after 2-3 minutes joomla shows blank page and have to go back to the administration home. In this case I find that has not uploaded any images.
I've tried using Explorer, Filezilla, Chrome: same result.
May depend on what? Can anyone help me?
Thank you.

Can you look at the error_log for any potential errors?

I attach a debug file: a couple of "Handler for (null) returned invalid result code 70014" and various "PHP Fatal error: Maximum execution time of 30 seconds exceeded", but these are likely to happen when I click on save.

In fact an image preview should be charged immediately, without clicking save? I assure you that is not the case, even if i select an image of 1KB.

I cannot see an attached file.
If the save function is not performed then the image will never appear.
The PHP Fatal error: Maximum execution time of 30 seconds exceeded
means that a script is using too many resources.

I suggest that you show this log to your hosting provider. He will be able to tell you which script/extension triggered this error.

All fixed!
First of all, I had misunderstood the functioning of image uploading.
Then the variable "max_execution_time" in php.ini was set to 30 seconds, and to upload an heavy picture , that value was increased.
Thank you and see you soon.

You 're welcome Roberto.
I 'm glad you solved it.