Apache Tomcat blank page served in Windows 7

I came across this problem when installing Aastra's IP phone software server. The service starts but an error 404 is given or a blank page is presented. The reason is that something else uses port 80. No other web server software installed? A lovely suprise from Windows! Go to services, and at the bottom is a Windows IIS service or Windows Web publishing! Disable it and restart your Tomcat service.

All should run fine.