Client PC deployment problems

Hi,

We are developing a .NET client application that integrates with Crystal Reports Server 2008.

On my development PC (with Visual Studio 2008 and Crystal Reports 2008) the application can access the report server with no problems.

However, on client PCs with the application deployed, we are getting the following error:-

Retrieving the COM class factory for component with CLSID {E063B04A-Cb8B-460E-99D0-F7D8FA2FAAA2} failed due to the following error: 80040154

We have deployed the Crystal runtime using CRRuntime_12_1_mlb.msi and also run the client tools installer from the server install.

What else needs to be installed on these PCs?

Thanks