You didn't list the 404 error, and in particular the URL.
If you were hoping that servlets could be found just by typing their names, that was an insecure feature that's no longer supported in Tomcat. You now need to explicitly define the servlet and its relative URL in web.xml.
An IDE is no substitute for an Intelligent Developer.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com