Charts not displayed on Enterprise XI 3.1

We are upgrading our Crystal Enterprise from 9 to XI 3.1 and our report development tool from 9 to 2008. We have some reports that generate a chart image along with the data. When running the report from Enterprise, the data appears but the charts do not show up. I can however open the report in CR 2008 and run it within the development tool and see the charts. The reports were originally created in CR 9, and I have tried saving them to the server in CR 2008 but get same results. The reports usually ran as PDF format, but running them as Crystal Reports format doesn't show the charts either.

Is there something we could be missing on the Enterprise server? A service pack or plug in? Any help you could give would be appreciated.

Thank you!