Is the button's image file where it's supposed to be? Is the file not broken? Are all permissions to download it set correctly? Can you see the file getting accessed in the access.log, and producing either a 200 or 304 response from the server? If you didn't change anything, it should be the file templates/default/images/en_US/post.gif.
What's with the strange bottom of the screen shot? Those icon explanations look broken.
It should be easy to figure out what's wrong. Right click on the images which aren't being displayed and view the source of the image (different browsers have different options, firefox says "View image info"). Make sure the source of the image is correct expected location and the image exists at that location.
subodh joshi wrote:But in Smilies its not possible thats why i was not able to figure out the issue its loading by some Java script.
I have download forum and install it today, and I meet same issue.This issue is language bug. If you set language to en_US when you install forum, all images could be right. The image link can't find object if you choose other language.
Solution is copy [jforum-path]/templates/default/images/en_US and rename to your language code(e.g zh_CN,pt_BR...).