i had hard time uploading >300kb photo, anyone can upload 1Mb photo or more? im not sure this is server issue or oxwall issue.
and spam alert on oxwall block me? what oxwall use for stop spam?
what kind of image is it, .jpg, .png, .gif ??
check your php ini and your htaccess for any settings that have to do with upload size, post size.
Also IMO 300k is still too big for an image, people need to know that you can get the same quality with a 20k image that you can with a 300k image, and think about all the diskspace your saving. :)
if we set our image size at 20kb no one would upload any pictures, even at 500kb we still have to reduce them to get on site,
can you attach the file, to this post what is the file name of the image
have you checked in content input in your admin area, in rich media settings, is it set the same as the photo plug in, we were caught out with this once before