News Template Image Issue

I've been getting a very annoy error in my website since the day i used your template, i searched every where on internet but i didn't found any solution that fix this issue, i attached a from page screen so you can see.
Error is = "An error occured during creating the thumbnail."
please help me, i really thankful of you.

Hi,

Please download the latest version of GK News Show Pro plugin:
https://github.com/GavickPro/GK-News-Show-Pro
, unzip and upload gk-nsp directory to your wp-content/plugins directory.

then, please resave your widget settings and check your images, if that won't help, please send me private message with your website backend and FTP access and I'll try to help.