Can you update your Joomla backend and FTP access at http://stackideas.com/dashboard/site so we can better have a check?

Also can you attach that image file where as what you trying to upload from your site?

Thanks for getting back to us your issue has been resolved now.

As a gentle reminder, kindly start a new thread if you have any other issue in the future so it will be easier for us to manage your inquiry. I will lock and mark this thread as resolved.