Portable Network Graphics are increasing in popularity across websites due to their clarity and support for multiple levels of transparency. Since version 7, Internet Explorer has been capable of displaying PNG files with transparency; however, a number of other issues, both in general and specific to IE 11, can hinder the viewing of PNG files. These include broken links and incompatible Web code.
Checking Broken Links
Problems with missing pictures on a website often relates to broken links. This is particularly true if IE 11 can see other images without issue. Right-click on an image that won't load and select "View Image." If you can't see the image after doing that, the image link might not be pointing to the right location. You can contact the webmaster or, if you are the webmaster, right-click on the image and select "Inspect Source." This will open up the code in a pane at the bottom of IE, and highlight the tag that's linking to the image. Within that tag, check the "src=" argument to ensure there are no typos, and that the address is an Internet-accessible address.
Checking Image Viewing Problems
Check to see if the issue is affecting certain PNG files, all PNG files, or every image file. In the latter two cases, there likely exists an incompatibility between the Web page's program and IE implementation of that programming. The best way to address this issue is to add the website to IE's compatibility view list. To do this, click or tap on the "Tools" button within IE, the one shaped like a gear, and then tap or click on "Compatibility View Settings." Once there, click on "Add this website," and paste the URL of any website that is having trouble loading images.
Checking Image Display Settings
It is possible that images won't display in IE due to an improper setting within the browser. To check these settings, tap or click on the "Tools" button and select "Internet Options." In the window that comes up, select the "Advanced" tab. Under this tab, you'll find a list of check boxes. Scroll through the list until you find the sub-heading "Multimedia" and ensure that "Show Pictures" has a check mark next to it.
Ensure IE Is up to Date
Microsoft has authored a website devoted exclusively to issues experienced with IE 11 (see Resources). These issues continue to be addressed by Microsoft through a series of updates. If nothing else fixes the PNG issue, make sure to download and install the latest version of IE 11. This should mitigate any issue relating to the browser itself.