2sxc: In app setting can't upload images

Question

I need to set a default image for my new app, so I was thinking about to use the app setting feature.
So I added a new content type of file type, but trying to upload a 20,3 KB file from adam it gives me the following error

The upload failed. The most likely cause is that the file you were trying to upload is bigger than the maximum upload size.

Using the image manager I'm able to upload my image and work with it.
It is an adam issue?
Thanks

Answer 1

most likely it's a forbidden file extension. Check fiddler / network-trafic to see what the real error is.