Ajax error

Hello,

I’m unable to use the plugin at all. I’ve used this successfully in the past. However, recently I’ve moved hosts (to SiteGround) and also upgraded to WP 4.0.

Now, whenever I try to import, I get this error: https://www.dropbox.com/s/tsl68vhs384nxjf/Screenshot%202014-10-05%2013.42.58.png?dl=0

Any help would be greatly appreciated.

Regards

https://ww.wp.xz.cn/plugins/woocommerce-csvimport/