The version of SharePoint Server 2010 for Internet Sites that is downloaded and installed before May 25, 2010 does not have all product features enabled, or it runs with reduced functionality

If you installed Microsoft SharePoint Server 2010 For Internet Sites Enterprise, and then you tried to activate the product by using the enterprise key before May 25, 2010, you encounter the following symptoms:

• The following Enterprise features are not available, or the features have reduced functionality:
  • Access Services
  • InfoPath Forms Services
  • Chart Web Parts
  • Excel Services
  • PerformancePoint Services
  • Visio Services

To verify that you are encountering this issue, consider the following scenarios:

• One of the following GUIDs exists in the output of the (Get-SPFarm).Products cmdlet:
  • 1F230F82-E3BA-4053-9B6D-E8F061A933FC
  • F48AC5F3-0E33-44D8-A6A9-A629355F3F0C
• The following registry subkey contains one of the previous GUIDs:
  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0\WSS\InstalledProducts\{90140000-110D-0000-1000-0000000FF1CE}

For more info and a solution look here : http://support.microsoft.com/kb/2143810