Why Can Fail?!
You have created a web based Crystal Report Viewer in the IIS default web site. Everything looks fine. However, when you move it to a different web site under a different application pool, the crystal report viewer button icons all goes missing, becoming red “x”s.
Why Like That?!
This is because the image icons for Crystal Report viewer actually reside in aspnet_client folder, rather than the application directory. It is already included in the default web site, (C:\inetpub\wwwroot\), so the buttons will appear with no issues. If you move it to a different web site without a reference to the aspnet_client directory, the crystal report viewer will be unable to find the images and display red “x”s.
What To Do?!
In your newly created web site, create a virtual directory reference called “aspnet_client” and point it to the original folder path (C:\inetpub\wwwroot\aspnet_client), with the same permissions.
Where Got Say?!
The solution is inferred from a few sources, which mentions copying the aspnet_client image files to your application directory. (Not a good idea IMO). Still, credit goes to them for figuring out the cause of the issue.
2 references are stated here
http://www.santry.com/Blog/tabid/90/ID/1153/Deploying-a-Crystal-Reports-Application-to-a-Remote-Server.aspx
http://social.msdn.microsoft.com/Forums/en/vscrystalreports/thread/e2dc93b3-e594-4ae6-ba92-9440ccc7f6be