problem with system object, please help

Hello there. can someone please help me out with the following question.
I have created an object in the designer and published it. Now i want to use it in the process, but i can't. It's impossible to publish the process with this object, it shows the error message "type not found".
Is that a bug or something else?

 

Try restarting the server. Usually you need to do that after creating and publishing objects.