You have exceeded the evaluation period of this product

I am getting you have exceeded the evaluation period error every time I try and log into our reporting service url.  I am able to access SQL Server just fine it is only Reporting Services I am having issues. Can anyone          let me know the best way to resolve it. This is the full error"

• An error occurred when invoking the authorization extension.
  (rsAuthorizationExtensionError) Get Online Help
  
  • You have exceeded the evaluation period of this product. Please upgrade to
    the retail version to continue using the product. For information on purchasing
    the retail version of this product, go to
    http://go.microsoft.com/fwlink/?LinkID=74446.