Not alot of people had these issues regarding the Claims to Windows Token Service, but I had some problems with it. For some reason on Windows Server 2008 with Service Pack 2 and all prerequisites installed except voor KB971831-x64 HotFix voor WCF c2wts couldn't be started. In the event viewer and in the ULS logs I had alot of messages that it takes too long to start te service.
Also when I browsed to the http://
For some reason or another it tries to make a connection to the outside world(internet) from the Service Application in order to get the ssl certificate, but this isn't possible when you are at a production network of a cliënt. So I checked the config file of the SecurityToken.svc and I found out that there is a .NET framework 4.0 mentioned in it. So I downloaded the .NET Framework 4.0 and installed it on the production servers hosting SharePoint.
After installation it worked without any problems. I don't know what fixes it, but it okay, because know we can use Excel Services as it should be.