If you use the web-based VMware Management Interface to control your ESX Server and you have problems when trying to open virtual machines when using Microsoft Internet Explorer 7, this might help you.

If you use IE7 and you find that rather than getting the open prompt you get the "find" option, you probably need to define the "application/x-vmware-console" MIME type so that IE7 knows how to open the file.

Make sure you have the application association defined correctly. You can check for or add the following registry key:

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/x-vmware-console]

Make sure the extension is there and defined as ".xvm" 

If not, add the information, save the registry and then reboot. VMware should then function correctly.

Thanks to Sanjay for the information.