SQL Server 2008 R2 SP1 - Can't install "Full-text Search"

I have a "Microsoft SQL Server Express 2008 R2 SP1" installation on a machine without the "Advanced Services". Now I want to install the "Full-text Search", so I downloaded the setup "SQLEXPRADV_x64_DEU.exe". The problem is, if I start the setup, select my existing sql-instance and go further to the feature-selection menu, I don't see the "Advanced Services". I just see the already installed features. Here's a screenshot (in german): I did the installation of the "Full-text Search" on about 20 different machines with existing sql-instances without problems. But on this machine, I don't know what's the problem. Hope somebody can help me! Thanks in advance!