Important note: on your PC, the PNG file extension must not be associated with or managed by a particular or specific software for opening PNG image file type. If this is the case, then the test may not work. In Windows Explorer, do Tools/Folder Options.../File Types tab/ and then, in the populated list, search for PNG and the "Opens with" setting should be set to "Windows Picture and Fax Viewer".
I ran the test and got the attached screenshot. I did have to allow a bit of Active X to run first though. Does this mean the test truly passes?
Which bit of ActiveX did you have to allow exactly?
Microsoft HTML Viewer, whatever that is.
when the information/warning toolbar pops up, it ask you to enable such Active X, right?
Yes. I only allowed it as I trust you.
If it helps, a Quicktime logo pops up briefly before the passed message appears. Perhaps it is expecting the object element to contain a movie or something, with PNG being a fallback image.
This text is displayed:
"Images download support must be enabled for this test. This test is passed if you see a clear and explicit message saying so.
Your browser does not support native image loading in <object> for PNG images. Your browser FAILED this test."
There is also a yellow bar with a message that the site wants to install Microsoft HTML viewer. If I allow that, the message "Your browser does not support native image loading in <object> for PNG images. Your browser FAILED this test." disappears but there is no message saying that the browser passed the test.
It works correctly, I see the image with the green text.
I get an ActiveX warning with the message "Microsoft HTML viewer...." when using IE7 on a machine where PNG files are managed by another application that I installed. And on another IE7 installation this doesn't happen (but I get scrollbars around the image, that's an old problem.)
I will try again with IE8 after installing something else and changing the PNG file association.
I tried again after installing Apple QuickTimePlayer (simple version, without ITune.)
Now with IE8b2 on your page I get (the first time) an ActiveX warning with the message "Microsoft HTML viewer....", if I allow this to run then the PNG is displayed correctly but I see a "flash" of a QuickTime logo, so I believe that now the PNG is displayed with a different mechanism (and it gets a grey border).
QuickTime installs an IE add-on (QuickTime object), if I disable it then IE8 is no more able to display the PNG in your page.
I didn't allow QuickTime to change the PNG file association, indeed it is still 'Windows Picture and Fax Viewer' in 'File Types', but the problem is triggered anyway.
QuickTime adds an entry in the Control Panel, here there is a 'File Types' tab where PNG is not selected, but there is also another tab called 'browser' with 'Mime Settings' and here PNG is checked (I had no choice about this during the installation).
Apparently 'Mime Settings' and 'File Types' are two separate settings. If I uncheck the PNG Mime Type in the Quicktime control panel then all comes back to normal: PNG not displayed using the add-on (no visible border), but 'natively'.