Tomcat v7.0 stopped to run my project at localhost

Question

I was working on my web application in eclipse with Tomcat v7.0, and everything was fine.
But today suddenly I can\'t run my poject on server anymore.
I do as usual:

Answer 1

I had similar problem, but java.lang.NullPointerException instead.

For me the only thing that worked was to:

1. Right-click on server instance on servers view -> Properties -> Switch Location;
2. Remove all published projects from server;
3. Right click on server again and do both cleans.

Hope that helps!