Cannot start Xampp on server with IIS

I am running a Windows Server 2003 with IIS and I am trying to install XAMPP in order to be able to run php and mysql based pages. I tried to install php on IIS, but it is too complicated and time consuming for me. I am able to run asp on localhost/ and I would like to run php websites on different port, say localhost:81/. After installing xampp and changing the port in httpd.conf 开发者_开发问答file to 81 I try to turn on apache, but it turns off after about 5 seconds. Mysql works fine. It seems that there is a port clash, but I do not know how to change the ports and turn the apache permanently. Any advice appreciated. (I know it is more a server fault question, however I posted it there as well and did not get any reply, so I decided to try here)

---

Change both Listen to 81 and ServerName to localhost:81

Also check Listen 443 in apache/conf/extra/httpd-ssl.conf, in case your IIS is also configured for ssl

You can also configure your IIS to serve PHP pages