title: .png images display in IE8 alone but not inside a page
body: <p>It's been a while since I did serious web development. Now I meet a host of brand new problems I'm no longer familiar with..</p>
  
  <p>I have some .png images for various icons in my web page. What I find is that whenever I edit these images, they stop working inside a page in IE8. That is, they (usually) display OK when I first open the page, then are replaced by the placeholder icon on refresh. Sometimes, some of the icons display and others, with the same src, don't.</p>
  
  <p>My image tags are nothing fancy, typically:</p>
  
  <pre><code>&lt;img src="images/misc/smallreport.png" alt="Report" /&gt;
  </code></pre>
  
  <p>When I right-click an icon in the page and select "properties", protocol, type, address and size are shown as "Not Available", and dimensions are incorrect (size of the placeholder, I bet).</p>
  
  <p>If I open the images directly in IE (ie. not within the page), they work just fine.</p>
  
  <p>I have used Paint.NET to edit the images, but have also tried saving them with Paint.</p>
  
  <p>Right now, I am working right off the hard disk (ie. not through a web server). And, oh yes, none of this happens in Google Chrome.</p>
  
  <p>What's going on here?</p>