Photos / Media Library – uploads fail

I run WordPress through a godaddy reseller with woocommerce installed and for the last few weeks, every single time I try to upload a photo, I get a failure ‘HTTP error’. I’m fully current with all updates.
The images are jpg format and are 1.58mb approximately. I took the images on my iphone 6. I also tried taking my images on a digital camera (Sony HX90V) but those images also failed to upload.
I’ve tried uploading the images to another godaddy hosted wordpress site and they upload with no problems whatsoever. The differences are 1) directly hosted 2) not woocommerce 3) different themes

So what’s going wrong? I’m a novice so please speak to me as though I’m an idiot.