I occasionally have problems with starting Tomcat from Eclipse. Eclipse WTP gives me the message:
Server Tomcat v6.0 Server at localhost was unable to start within 45 seconds. If the server requires more time, try increasing the timeout in the server editor.
While searching the web I found that others also have the problem hence this blog post.
Via a Eclipse forums post I recently learned how I could analyse the the problem.
Larry Isaacs explains:
The lack of output in the Console view suggests that the attempt to launch Tomcat is failing. After attempting to start Tomcat, switch to the Debug perspective and look in the Debug window. You should see a terminated launch. You can right-click on the nested item under the terminated launch and select Properties. This should display the command line that is being used to launch Tomcat. You could try that command in a terminal window to see what happens.
Eclipse uses javaw so you have to change it to java, as javaw will not open a console or log anything to an existing console (as Larry also explains in the forum post).
I hope this helps to identify the problem. I personally restarted my Laptop and ran Eclipse with -clean and now Tomcat starts again without problems.