I'm not talking about VS on the web server - I'm asking what did you use to develop the application? I don't think .NET 4.0 is available in VS 2008 where the Crystal 2008 runtime is supported. So, if you're targeting .NET 4.0, either VS 2010 or 2012 was used to develop the application. So, even though you might be able to "see" and use the Crystal 2008 (version 12.x) components in those versions of VS, it's not officially supported and you probably will not be able to get assistance with your issue.
-Dell