Document icons not visible in sharepoint 2010

Hi

I am working on sharepoint 2010. I have a site in which document icons are missing. Example: When going into View All Items -> Pages , the pages should be having "IE" icon to be displayed. Similarly for word , css files . All the icons are showing as "X". I have checked the DOCICON.XML file to be correct (compared to file present in other server).

When trying to access the image directly eg: http:localhost:99/_layouts/images/ichtm.gif , i am able to access the image without issue.

When looking at the properties of the image, i could get the url as http:localhost:99/_layouts/images.

Please help me to resolve this issue.

Thanks in advance

Usha