mdivk wrote:
I am not sure why it's working this way, I would say this is a bug from my experience: once a file (in my case it is a screenshot image) is attached to a post, you won't be able to remove it from the post, you edit the post, go down to the attachment section, and remove it, ok, it seems to have been removed, once you hit submit button to update the post, you will see the attachment is still there.
If this is a design requirement, then at least the remove feature should be disable so people won't get misled.
Please correct me if I am wrong.
Thanks.
No your not wrong. I actually have a ticlet in for that. Here is my workaround, convoluted as it is 
1) you've uploaded your image and set the attachment code in the editor. Saved and then realized you don't like the graphic.
2) so remove the old attachment code and upload your new graphic.
3) set the new attachement code in the editor.
4) SAVE
5) edit the Topic and this time on the old image -> upper LH corner is a lock -> click it to make the image only show in the Secure tab. The image overlay turns yellow
6) SAVE
7) edit the Topic and this time on the yellow locked image click REMOVE at the bottom.
SAVE
Now your unwanted image is gone