We are currently investigating issues some players are having logging into the European PC/Mac megaserver. We will update as new information becomes available.
Make sure you have the materials as well. I've accidentally forgotten to make sure I have enough more then once.
If you need to, uncheck the 'materials' and 'knowledge' at the top. It'll show you all the options available. If you have the knowledge and the materials and it's still not showing up, logging in and out usually fixes that for me.