Default Host Application error

Last week I was called up by one of our Windows Admins. He had some issues with a VM running Windows and IIS. As we were talking he also casually mentioned another error he was seeing that was “caused by VMware”. I was a bit sceptic as you might imagine 🙂

He was seeing this error when he attempted to browse the IIS web page by clicking the link available in the IIS Manager:

Default Host Application ErrorNotice the VMware icon in the bottom. This is an error from VMware tools! What? As any sane person would do I consulted Google. And got a hit here –

The third reply post gave me the answer. Seems that when installing VMware Tools it might associate itself with HTTP and HTTPS links. This would then cause a click on the link in IIS Manager to call VMware Tools which is unable to service the request. The fix is pretty straight forward.

Go to Control Panel, then Default Programs and Set Associations. Scroll down to the Protocols section and locate HTTP and HTTPS. Make sure these are set to your browser of choice – in the image below I set them back to Internet Explorer (he was a Windows Sysadm after all 🙂 ). If the association is wrong it would be set to Default Host Application as shown for TELNET.