I recently ran into an issue when attempting to install Dynamics CRM 2011 RTM.  The error I was getting was “MsiOpenPackage failed.”  This was popping up when I tried to run the SetupServer.exe, even with admin rights which seemed like a strange error.  It turned out that the CRM 2011 RC version was already installed on this server.  The fix was to uninstall the RC version, and then run the SetupServer.exe again for the RTM version.  Once RC was uninstalled, then the installation for the RTM version ran just fine.