Cannot start service spusercodev4 on computer

I tried to deploy a sandbox solution out of Visual Studio 2010 and received the following error:
cannot start service spusercodev4 on computer
Somehow the "Microsoft SharePoint Foundation Sandboxed Code Service" in Central Administration stopped.
Go to Central Administration -> System Settings -> Manage services on server and pick there the service mentioned above and restart. I read on another blog, that also the "Microsoft SharePoint Foundation User Code Service" service might cause this trouble. If my solution does not work, please refer to this blog:
http://blog.dennus.net/2009/11/18/sp2010-spusercodev4-your-new-web-part-project-isnt-deploying/